# species_source

externallink: https://www.biodiversitylibrary.org/item/71437#page/15/mode/1up
description:
  Rhabdophaga gnaphalioides

  Cecidomyia salicis-gnaphalioides

  A monothalamous, solitary, oval gall, terminal on twigs. It consists of closely overlapping leaves, much dwarfed, the tips pinched together to form a beak, and spreading. About 1 cm long. Yellow-brown with the outside of each leaf so covered with appressed, whitish hairs as to look silvery. Gall formed in summer, insects appearing in late April or in May. On willow, Salix.


externallink: https://www.biodiversitylibrary.org/item/71437#page/16/mode/1up
description:
  Cryptocampus nodus

  Euura salicis nodus
  Cryptocampus salicis-nodus

  A gradual enlargement of the twig, usually around the twig, and several near one another. Polythalamous. From twice to several times the diameter of the twig. 1-3 cm long. Larvae sometimes remain in gall over winter, sometimes go under ground. Emerge in April or May. On willow, Salix sp.


externallink: https://www.biodiversitylibrary.org/item/71437#page/15/mode/1up
description:
  Cryptocampus cooperae

  [Salix interior added as a placeholder]

  A roughened, irregular, many-celled gall, rising very abruptly from the side of the twig. Woody, knotty. Two or more crowded together, or occurring singly, 5-15 mm long, 5-10 mm wide. On willow, Salix. September.


externallink: https://www.biodiversitylibrary.org/item/71437#page/16/mode/1up
description:
  Cryptocampus ovum

  Euura salicis-ovum
  Euura ovum
  Cryptocampus salicis-ovum

  This monothalamous gall consists of a deformed bud the tip of which persists. The gall varies considerably in size and shape, sometimes nearly spherical, again elliptical or ovoid, and tapering. When mature the larval cell is surrounded by a red-brown spongy mass, containing fibers transverse to the stem. Rather common on willow, Salix sp. Insect remains as larva during winter. Some apparently pupate underground. Imago in April.


externallink: https://www.biodiversitylibrary.org/item/71437#page/16/mode/1up
description:
  Nematus pomum

  Nematus salicis-pomum

  Rounded, fleshy leaf-gall, about 1 cm in diameter. Green with rosy cheek. Appears early in the spring, matures by late July. Insect emerges the following April. Common on heart-leaved willow, Salix cordata.


description:
  Rabdophaga salicisbatatus
  Tuber-gall midge

  This midge induces large, integral, polythalamous, tuber-like stem galls on several species of willow in the West.


description:
  Rabdophaga salicisbrassicoides
  Rosette-gall midge

  This midge induces open or closed rosette, polythalamous bud galls on several species of willow.


description:
  Rabdophaga strobiloides
  Cone-gall midge

  This midge induces pinecone-like, monothalamous galls on lateral and terminal buds of several species of willow throughout western states.


description:
  Rabdophaga sp.
  Bud-gall midge
  [Page 213]

  This midge induces cone-shaped, monothalamous bud galls on members of the arroyo willow (Salix lasiolepis) group.


description:
  Euura breweriae
  Brewer's-stem-gall sawfly
  [Page 213]

  This sawfly induces linear, lopsided, integral, polythalamous stem galls on Brewer's willow (Salix breweri).


description:
  Euura exiguae
  Stem sawfly
  [Page 214]

  This sawfly induces linear, gradually tapering, integral stem galls on narrowleaf willow (Salix exigua) and dusky willow (Salix melanopsis) and possibly other related species.


description:
  Euura geyerianae
  Geyer's stem-gall sawfly
  [Page 214]

  This sawfly induces bulbous, abruptly swollen, integral stem galls on Geyer's willow (Salix geyerianae).


description:
  Euura lasiolepis
  Stem-gall sawfly
  [Page 214]

  This sawfly induces thick-walled, lopsided, integral stem galls on arroyo willow (Salix lasiolepis).


description:
  Euura lemmoniae
  Lemmon's stem-gall sawfly
  [Page 215]

  This sawfly induces abruptly swollen, potato-shaped, integral stem galls on Lemmon's willow (Salix lemmonii).


description:
  Euura scoulerianae
  Scouler's stem-gall sawfly
  [Page 215]

  This sawfly induces thick-walled, elongate, smooth, integral stem galls on Scouler's willow (Salix scouleriana).


description:
  Euura sp. A 
  Petiole-gall sawfly
  [Page 216]

  Host: Salix lasiandra

  The surface of the gall is generally glabrous but with distinct rounded cross ridges or furrows.


description:
  Euura sp. B
  Smooth-petiole-gall sawfly
  [Page 216]

  The smooth, glabrous, monothalamous galls of this sawfly occur on the short petioles of leaves of Barclay's willow (S barclayi) and perhaps other species in the subalpine environment of mountains.


description:
  Aculops tetanothrix
  Bead-gall mite
  [Page 217]

  This mite induces irregularly rounded bead galls on both sides of leaves of several species of willow from Utah and Arizona to California.


description:
  Unknown #3
  Midrib-gall sawfly
  [Page 219]

  Host: Salix spp [Salix planifolia listed as a placeholder]

  Galls are asymmetrical, bulging out on one side of the ventral midrib and are at least three to four times larger than the normal vein.

  Range: Pacific States


description:
  Iteomyia sp. A
  Tooth-gall midge
  [Page 220]

  Hosts: Salix lasiolepis and related willows.

  Each gall is characterized by one or more slightly bent projections that look like roots of a molar tooth.


description:
  Pontania californica
  Willow-apple-gall sawfly
  [Page 222, Plate 374]

  Hosts: Salix lasiolepis and lemmonii groups

  "While glabrous and generally smooth, these galls do possess minute, wart-like scales or tubercles called LENTICELS. This species is the only sawfly gall-inducer in the West with galls bearing such lenticels."

  Range: throughout the West and as far north as the Alaskan tundra


description:
  Phyllocolpa sp.
  Fold-gall sawfly
  [Page 223]

  Host: Salix spp.

  The simple fold occurs along only one margin of the leaves, often turning inward toward the ventral midrib in a circular manner.


description:
  Euura proxima

  Nematus proximus
  Pontania proxima
  Nematus gallicola
  Nematus vallisnierii
  Nematus redii
  Pontania gallicola
  Messa hyalina
  Euura flavipes
  Pontania daedala

  Bionomics. Host plants: Salix alba, S. × fragilis, S. × rubens, S. babylonica (Kopelke 2005; a rarely used host, or misidentified, according to Zinovjev 1999), S. blanda (Halstead 2001), Salix × meyeriana (= Salix pentandra × euxina), S. euxina (Zinovjev 2011), S. fragilis × pentandra (Mol 2013), S. excelsa (Özay 1997). According to Zinovjev (1999: Table 5), rare records (e.g. Conde 1938) of proxima group galls from S. pentandra are probably attributable to E. proxima, because this willow belongs in the subgenus Salix, like the other host species of E. proxima, whereas E.bridgmanii is restricted to hosts of subgenus Vetrix

  Range: Europe; Introduced  to  N.  America,  Australia  and  New  Zealand


description:
  Large, tan-brown, striated, potato-like irregularly globular swellings along the stem of Salix sitchensis. Similar to Russo's drawing of [Euura lemmoniae](https://www.gallformers.org/gall/3622). Observed in Washington in June.


description:
  Small red hairy bead galls visible but not protruding on the upper and lower sides of lateral veins of Salix discolor. Observed in Minnesota in June.


description:
  A similar gall has been observed on a willow identified as [Salix sitchensis](https://www.inaturalist.org/observations/27415426).


description:
  Two similar galls have been observed in Washington, one on Salix scouleriana in [June](https://www.inaturalist.org/observations/82122787) and one on Salix sitchensis in [September](https://www.inaturalist.org/observations/94885577). Both are short, cylindrical galls between veins on the lower side of the leaf with a distinct circle at the apex, sparsely covered in hairs, pale green to yellow in color, leaving a discolored circle on the upper side. 


description:
  [Undescribed species]

  Quercus garryana
  Flower galls
  Enlarged filament bearing anthers, globular, mottled, 1.8 mm. May. Fig 185.

  Fig 185. Unknown flower gall on Q. garryana from Ft. Jones, Calif. on May 25. Diameter 1.8 mm. A guest fly, Synergus sp., emerged June 26.


description:
  A large globular gall completely covered in long white wool, resembling a cotton ball. Apparently always found in pairs on either side of the midrib of a willow tentatively identified as Salix bebbiana. Where the wool is worn away, the gall is red-tan-brown. Integral, showing slightly on the top of the leaf but predominantly below the leaf. Observed in Yukon in June and July.


externallink: https://www.biodiversitylibrary.org/page/16194684#page/373/mode/1up
description:
  Pontania gracilis

  Type locality: Virginia

  Host plant: Salix sericea

  Notes. — This is a valid species of Pontania (Eupontania). The description of P. gracilis larvae and biology by Dyar (1897b) refers to P. petiolaridis Rohwer. A typical gall of this species is shown in Fig. 3 (from Otsego Co., N.Y., collected by AGZ and R. Fritz). 


externallink: https://www.biodiversitylibrary.org/page/16194684#page/373/mode/1up
description:
  Pontania nigrita

  Type locality. — Michigan. The holotype is labeled "Ag. Coll. Mich," presumably from East Lansing. 

  Host plants. — According to Smith and Fritz (1996), the host plants are Salix seri- cea, S. discolor Muhl., and S. eriocephala Michx. 

  Notes. — This is a valid species of Phyllocolpa and belongs to the leucosticta group. Its larva and biology were described by Dyar (1897b) under the name Pontania pallicornis Norton.


externallink: https://www.biodiversitylibrary.org/page/16194684#page/373/mode/1up
description:
  Pontania populi

  Type locality. — New York

  Host plant. — Populus grandidentata Michx. 

  Notes. — A valid species, Pontania {Pon- tania) popidi Marlatt, belonging to the crassispina group. The larvae and biology were described by Dyar (1897a). It produces leaf rolls on the host creating a small swelling (procecidium) at the site of egg laying. There is more than one generation per year. The larvae eat the parenchyma and leave the upper cuticle intact, which is typical for species of the crassispina group. A very slight ventroapical indentation of the sheath (Fig. 11) and the leaf-folding habit led to the inclusion of this species in Phyllocolpa by Smith and Fritz (1996). 


externallink: https://www.biodiversitylibrary.org/page/16194684#page/373/mode/1up
description:
  Pontania robusta 

  Type locality. — "Michigan and District of Columbia (?)." The lectotype is labeled "Ag. Coll. Mich.," presumably East Lansing. 

  Host. — Populus tremuloides Michx. 

  Notes. — This is a valid species of Phyllocolpa in the leucapsis group. The larva and biology were described by Dyar (1897b). It produces leaf folds on aspen, as was confirmed by Smith and Fritz (1996). There is one generation a year. 


externallink: https://www.biodiversitylibrary.org/page/16194684#page/374/mode/1up
description:
  Pontania terminalis 

  Type locality. — Near New York City. 

  Host plant. — Salix sericea, according to Smith and Fritz (1996). The host plant relationships of P. terminalis need to be confirmed. There is possibly more than one- species under this name. 

  Notes. — The valid name is Pontania (Pontania) terminalis Marlatt, and it belongs to the crassispina group. The larvae and biology were described by Dyar (1897a). It produces leaf rolls on willow similar to P. populi except with a smaller swelling at the site of egg laying. The larvae eat parenchyma and leave the upper cuticle intact, which is typical for this species group. The slight ventroapical indentation of the sheath (Fig. 12) and leaf-folding habit led to the placement of this species in Phyllocolpa by Smith and Fritz (1996).


externallink: https://www.biodiversitylibrary.org/page/16194684#page/374/mode/1up
description:
  Pontania (Eupontania) s-desmodioides

  Pontania borealis 

  Type locality. — Plattsburgh, N.Y, according to Dyar (1898). 

  Host plant. — Salix humilis Marsh, as determined by G. Argus (not Salix sericea as reported by Dyar). 

  Notes. — The valid name is Pontania (Eupontania) s-desmodioides (Walsh) (= Pontania borealis Dyar, n. syn.). Dyar's (1898) description of the galls is very similar to those described by Walsh (1866) for P. s-desmodioides. The host plant was misidentified by Dyar. The remnants of leaves with the galls of this species collected by Dyar are shown in Figs. 4, 5. The leaf shape and pubescence of those associated with P. s- desmodioides is typical for Salix humilis, and the willow identification was confirmed by G. Argus. However, along with these galls of P. s-desmodioides (Figs. 4b, 5a), there are also two others on the same pins which appear to belong to P. s-pomum (Figs. 4a, 5b). A typical P. s-pomum gall is in Fig. 2. The remnants of the leaves attached to the latter two galls are glabrous and might be Salix eriocephala Michx., the host plant of P. s-pomum. However, none of the three reared females can be identified as P. (E.) s-pomum. 


externallink: https://www.biodiversitylibrary.org/page/16194684#page/378/mode/1up
description:
  Pontania consors 

  Type locality. — Plattsburgh, N.Y. 

  Host plant. — Salix humilis as identified by G. Argus (not Salix sericea as reported by Dyar). 

  Notes. — This is a valid species, Pontania (Eupontania) consors Dyar. Dyar described the species as follows: "Galls found with the preceding on S. sericea, but gregarious, hairy and spherical. Near the base of the leaf, three or two together, rarely but one, exceeding the margin often by half the diameter of the gall; not evenly divided by the leaf, about one third or a little more above, two thirds below; pale greenish, often heavily marked and mottled with red above, paler below, rarely uniformly pale. Strongly silky hairy like the leaves below, less hairy or even smooth above; size 8.5— 8.5—7 mm or as small as 5 mm in diameter." The host plant was misidentified by Dyar. The remnants of the leaf were identified by G. Argus, as in the preceding case (P. borealis), as Salix humilis. A. G. Zinovjev and H. Goulet collected galls of P. consors at Lake Jean Venne, Masham Co., Quebec, Canada (about 50 km N of Ottawa) in the fall of 1995 on Salix humilis (host-plant determined by G. Argus).


externallink: https://www.biodiversitylibrary.org/page/16194684#page/378/mode/1up
description:
  Pontania amentivora 

  Type locality. — Falls Church, Virginia. 

  Host plant. — Salix sp. [Salix exigua used as a placeholder]

  Notes. — According to Rohwer "this species lives, in the larval stage, in the pistil- late catkins of a small species of Salix and causes the destruction of the ovaries and the premature forming of 'cotton'." This species is currently placed as a synonym of Amauronematus amentorum (Forster) (Smith 1979). The catkin feeders, including this and some related species previously placed in Amauronematus Konow belong in the genus Pontoprista Malaise. 


description:
  Aculus laevigatae

  Aculus vallis
  Vasates michineri
  Phyllocoptes laevigatae
  Vasates laevigatae

  Hosts: Salix laevigata, amygdaloides, hookeriana, matsudana, nigra, sp.

  Relationship: Beadlike leaf galls with lower surface openings.

  Range: CA, KS, FL, GA, OH, SD, WA; China

  Notes: There may be more than one species under this name


description:
  Aculus micheneri

  Vasates micheneri
  Vasates michineri

  Hosts: Salix nigra

  Relationship: In distorted flower buds.

  Range: KS


description:
  Aculus niphocladae

  Aculops niphocladae

  Hosts: Salix niphocladae, babylonica, koreensis

  Relationship: Galls; the mites cause bead galls on the leaves

  Range: Inuwik NW Territory, Canada

  Notes: Are they all the same species, in India, Japan, Korea and Arctic Canada?

  The hosts are ornamentals and shade trees in North America.


description:
  Aculus oresterae

  Aculops oresterae

  Hosts: Salix orestera

  Relationship: Irregular, globular, cavernous leaf galls protruding from lower leaf surfaces.

  Range: CA


externallink: https://www.biodiversitylibrary.org/page/50337404#page/455/mode/1up
description:
  Eriophyes salicicola

  Phytoptus salicola

  Host: Salix longifolia [interior]

  Leaf-gall, tiny, globular to irregular, often massed, on either surface of leaf, at times projecting through. .25-3 mm. across. Light green to completely crimson. July. Common.


externallink: https://www.biodiversitylibrary.org/page/50337404#page/455/mode/1up
description:
  Eriophyes aenigma

  Cecidomyia salicis-aenigma
  Acarus salicis-aenigma

  Host: Salix longifolia [interior]

  Terminal bud-gall, made up of an irregular cluster of yarn-like masses, each about 1-2 mm. in diameter, the whole 2x3 cm. Whitish tomentose, turning brown and remaining in situ. July. Fairly common.


externallink: https://www.biodiversitylibrary.org/page/50337404#page/456/mode/1up
description:
  Rhabdophaga brassicoides

  Cecidomyia salicis-brassicoides
  Cecidomyia brassicoides

  Host: Salix longifolia [interior]

  Twig-gall, evident as telescoping of terminal twig-structures, with abnormal down-production, and great broadening of leaves, whole extending back 10 cm. or more. Frequent. 


externallink: https://www.biodiversitylibrary.org/page/50337404#page/456/mode/1up
description:
  Rhabdophaga strobiloides

  Cecidomyia strobiloides
  Cecidomyia salicis-strobiloides

  Hosts: Salix longifolia [interior]

  Terminal bud-gall, showing as a rounded conical mass of closely appressed scale-like leaves. Green, with a whitish silky covering. 2.5-3 x 4 cm. Usually abundant, but scarce this year.


externallink: https://www.biodiversitylibrary.org/page/50337404#page/456/mode/1up
description:
  probably Cryptocampus nodus

  Euura salicis-nodus
  Cryptocampus salicis-nodus

  Host: Salix sp.

  Twig-gall, being a spindle-shaped enlargement of the herbaceous or young woody twigs, concentric with the stem as a rule, about 1 cm. in diameter, and ranging up to 3.5 cm. in length. Color that of normal twig.


externallink: https://www.biodiversitylibrary.org/page/50337404#page/456/mode/1up
description:
  Pontania pomum

  Nematus salicis-pomum
  Nematus pomum

  Hosts: Salix longifolia [interior]

  Leaf-gall, spherical to spherical constricted, on lower surface, and projecting slightly through. 5-10 mm. diameter. Color ranging from light green to red, depending upon light relation. Minute cork-specks frequently present. Very common. July 1st.


externallink: https://www.biodiversitylibrary.org/page/50337404#page/456/mode/1up
description:
  Pontania desmidoides

  Nematus salicis-desmidoides
  Nematus inquilinus
  Pontania inquilinus

  Leaf-gall, flattened bean-shaped, bisected by leaf, usually centered on a lateral vein, one to several galls on a leaf. 5-8 mm. long, 4-5 mm. broad and thick. Color various, usually crimson. Abundant in a restricted area. July 23. 


externallink: https://www.biodiversitylibrary.org/page/33339925#page/69/mode/1up
description:
  Cecidomyia triticoides

  Host: Salix sp.

  May-June. Remote resemblance to head of wheat. End of branch aborted making a dense tuft of small leaves.

  Range: MA


externallink: https://www.biodiversitylibrary.org/page/33339925#page/69/mode/1up
description:
  Phytoptus sp. [tentatively assigned to A tetanothrix]

  Willow, Mass. May. Elevated, irregular masses," single or compound; on upper side of leaf and more rarely below. Both positions on same leaf. Green or red according to host willow.


externallink: https://www.biodiversitylibrary.org/page/33339925#page/69/mode/1up
description:
  Cecidomyia rigidae

  Phytophaga rigidae

  Willow club gall. Mass. June. O. S. calls this "Cecid. siliqua." Egg evidently laid in terminal bud which is excavated by the larva burrowing downward. Top appears to lie always open, plate 21, 42.


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  Nematus pomum

  Willow. Mass. June. Rounded, yellowish on under side of leaf. Sawfly larva, single cell.


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  Cecidomyia verruca

  Salix humilis. Mass. Oct. Dome shaped, glabrous, above; turret-like, below. Cells in level of leaf proper.


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  [Unnamed] Probably acarus.

  Salix enigma. Willow mop gall. Mass. Oct. Aborted branch; twists to a dense, dark grey mop of dried leaves. Inner ones short and smooth, outer very hairy


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  Cecidomyia nodulus

  Willow species. Mass. May- June. Like club-gall, but less abrupt and does not destroy growth of stem.


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  Cecidomyia batatas

  Rhabdophaga batatas

  Willow, Mass., R. I. May-June. Galls strung along stem; irregular, woody


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  Nematus desmodioides

  Weeping willow. Mass. Late June, Oval excrescence above and below leaf blade.


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  Cecidomyia strobiloides

  Rhabdophaga strobiloides

  C. strobiliscus. Willow species. C. strobiloides Mass., N. H. June- July. Pine cone forms on stem.


externallink: https://www.biodiversitylibrary.org/page/33339925#page/70/mode/1up
description:
  [Undescribed. Genus assigned to Iteomyia based on appearance.]

  Willow [Salix discolor assigned as a placeholder]

  Mass. July. Conical, smooth above leaf; fleshy with small cavity below. 


description:
  Short sections of tightly rolled leaf edge on a willow tentatively identified as Salix amygdaloides. Observed in October in Minnesota.


externallink: https://www.biodiversitylibrary.org/page/16194684#page/380/mode/1up
description:
  Pontania leavitti 

  Type locality. — Nerepis, New Brunswick. 

  Host plant. — Salix sericea, according to Smith and Fritz (1996). 

  Notes. — A valid species of Phyllocolpa in the leucosticta group. The larvae form leaf rolls on Salix sericea and perhaps some other willows.


externallink: https://www.biodiversitylibrary.org/page/16194684#page/380/mode/1up
description:
  Pontania lucidae 

  Type locality. — Toronto, Ontario, Cana- da. 

  Host plant. — Salix lucida (original identification confirmed by G. Argus). 

  Notes. — A valid species in Pontania (Eupontania), closely related to Pontania consors as was stated by Rohwer. The examined leaves of Salix lucidae bear only a few typical leaf galls associated with midribs. The rest of the galls in this sample might rather be called petiole or midrib galls (Fig. 8). We are not sure if all of these galls belong to the species described by Rohwer or if some of them are Euura galls.


externallink: https://www.biodiversitylibrary.org/page/16194684#page/380/mode/1up
description:
   Pontania petiolaridis 

  Type locality. — Toronto, Ontario, Canada.

  Host plant. — Salix petiolaris Sm. (identification confirmed by G. Argus). 

  Notes. — This is a valid species in Pontania (Eupontania), is very closely related to P. gracilis, and has galls (Fig. 9) similar to those of P gracilis (Figs. 3, 6). The galls and biology were described by Cosens (1917) and probably by Dyar (1897b) under the name Pontania gracilis (host-plant "Salix petiolata") from Van Cortland Park, New York City, and Gouverneur, N.Y., on "Salix petiolata." The name "petiolata" is obviously a misprint for S. petiolaris (G. Argus, personal communication). Also, the remnants of leaves with the galls are glabrous and might belong to S. petiolaris. A. G. Zinovjev reared this species from galls collected by R. Vanderkam near Ottawa, Ontario, in 1995. 


description:
  Acalitus maracai

  Aceria maracai

  Hosts: Pluchea odorata, Neurolaena lobata

  Relationship: Galls on underside of leaves

  Range: Venezeula

  Notes: Both hosts are found in North America; Pluchea odorata is widespread; Neurolaena lobata is found in FL, USA, and in Puerto Rico and the Virgin Islands.


description:
  Many small irregular bead galls embedded in the lamina of leaves of Pluchea carolinensis, protruding slightly more from the lower side of the leaf. Observed in Florida in August and January. 


description:
  Phytophaga tumidosae

  Host: Salix sp.

  The galls were one-eighth to three-eighths of an inch long (Fig. 1) and were roughly spherical to oval in shape. The bark of a gall was scarred by shallow furrows running along its length. At its upper end each gall bore the scales of a withered bud or an oval scar from which the scales had fallen. Flanking the scar were two rounded swellings of incipient buds. Many of the galls were separately developed along the twigs, being well apart from one another, hut in some cases they were crowded against one another so that three or four galls occupied one inch of the length of the twig, and in several instances a number of adjacent galls had coalesced to form an irregular swelling one or two inches long, along the length of a twig. 

  [Two drawings of cross sections of this gall appear on page 2 of the pdf]

  Range: London, Ontario


externallink: https://www.biodiversitylibrary.org/page/16172889#page/507/mode/1up
description:
  Euura salicisgemma

  Valid name. — Euura orbitalis Norton 1862 (= Euura salicisgemma Walsh, synonymized by Norton 1867). 

  Host. — According to Walsh (1866b: 248, 250), this species creates bud galls on Salix humilis Marsh. 

  Notes. — We studied specimens from Canada (Quebec and Ontario) and U.S.A. (Illinois, Missouri, New Hampshire, and New York).


externallink: https://www.biodiversitylibrary.org/page/16172889#page/507/mode/1up
description:
  Euura salicisovum 

  Valid name. — Euura salicisovum Walsh. 

  Host. — According to Walsh on "S. cordata.'' Its currently accepted name is Salix eriocephala Michaux (= cordata Muhlenberg not Michaux) (Argus 1997). The galls are "monothalomous, spongy, growing from the side of the twig." Galls obviously belonging to this species were common on S. eriocephala around Ithaca, NY, in 1997 (Fig. 10). 

  Notes. — For further notes, see also Euura salicisovulum Walsh. 

  Euura perturbans 

  Valid name. — Euura salicisovum Walsh (= Euura perturbans Walsh). 

  Notes. — Euura perturbans was synonymized by Marlatt (1896). We consider this a color variation and accept the previously proposed synonymy under E. salicisovum.


externallink: https://www.biodiversitylibrary.org/page/16172889#page/509/mode/1up
description:
  Euura salicisovulum

  Valid name. — Euura salicisovulum Walsh. 

  Notes. — The galls are the same as those of Euura salicisovum; the larvae, according to Walsh, are distinguished from those making galls on Salix eriocephala being "all decidedly pale greenish," while those of E. salicisovum were "all decidedly yellowish." No galls were found by Walsh on Salix discolor which is closely related to S. humilis. 

  The taxonomic status of this species and its host plant specificity are not quite clear. Galls of this type occur not only on Salix eriocephala and S. humilis (including var. tristis), as stated by Walsh, but also on S. discolor and S. petiolaris. All such galls seem to be associated with a bud, which is however left unmodified, the swelling always situated just below the bud. 

  Specimens that seem to be conspecific with E. salicisovum are known from Illinois and Virginia, but all of them are either captured or reared from undetermined willows. We are not sure if they belong to E. salicisovum or to the complex of the sibling species involving E. salicisovulum. Thus, we cannot designate a neotype yet. 


externallink: https://www.biodiversitylibrary.org/page/16172889#page/510/mode/1up
description:
  Euura salicisnodus

  Valid name. — Euura salicisnodus Walsh. 

  Host. — According to Walsh '"Salix longifolia.'' Its currently used name is either Salix interior Rowlee (= longifolia Muhlenberg) or Salix exigua ssp. interior (Rowlee) Cronquist (see Argus 1997). The galls are "a mere enlargement of the twig, polythalamous, pitchy inside, with its cells all internal" (Fig. 12). 

  Notes. — This species is probably related to E. atra Jurine, a species introduced from Europe together with its host plants Salix alba L. and S". fragilis L. and their hybrids. Euura salicisnodus is separated from E. atra by its extensive paler coloration and the galls which form an enlargement of the twig. Euura atra does not produce enlargements of the twig; its galls are practically unnoticeable. Examined specimens are from Illinois, New York, Michigan (?), Ohio, and Canada (London, Ontario). Two species described from the western United States, Euura macgillivrayi Rohwer and Euura exigua E. L. Smith, are associated with the same willow species (or very closely related ones) and they might prove to be only geographical forms of E. salicisnodus.


externallink: https://www.biodiversitylibrary.org/page/16172889#page/511/mode/1up
description:
  [In the entry for [Euura salicisnodus](https://www.gallformers.org/gall/3576)]

  Notes. — This species is probably related to E. atra Jurine, a species introduced from Europe together with its host plants Salix alba L. and S. fragilis L. and their hybrids. Euura salicisnodus is separated from E. atra by its extensive paler coloration and the galls which form an enlargement of the twig. Euura atra does not produce enlargements of the twig; its galls are practically unnoticeable. 


externallink: https://www.biodiversitylibrary.org/page/16172889#page/513/mode/1up
description:
  Eupontania salicispomum, new combination

  Nematus salicispomum

   Valid name. — Eupontania salicispomum (Walsh), new combination. 

  Host. — The galls are on Salix eriocephala Michaux (= S. cordata). A subsidiary host plant might be Salix discolor Muhlenberg. Walsh wrote about it as follows: "On S. cordata, (and very rarely on Salix discolor)"; he found galls of Nematus salicispisum and galls "so identical in appearance with S. pomum"' on the same bushes." "In both the above two cases a few discolor bushes were growing in the midst of very large numbers of S. cordata, the species on which S. pomum is normally found." These data on its host plant specificity seem to be reliable, but confirmation by rearing adults is needed. 

  The galls are roundish (apple-like), transected by the leaf blade with a large part of the gall visible from the upper side of the leaf, but the larger part of the gall is situated below leaf surface (illustrated by Zinovjev and Smith 1999: 361, fig. 2). 

  Nematus hospes

  Valid name. — Eupontania salicispomum (Walsh) (= Nematus hospes Walsh). 

  Notes. — According to Walsh "absolutely undistinguishable from the normal type of the gall-making N. s. pomum.'' Marlatt (1896) synonymized N. hospes, and these species have always been treated as conspecific.


externallink: https://www.biodiversitylibrary.org/page/16172889#page/513/mode/1up
description:
  Eupontania salicisdesmodioides, new combination

  Nematus salicisdesmodioides

   Valid name. — Eupontania salicisdesmodioides (Walsh), new combination. 

  Host. — Salix humilis Marshall. 

  Notes. — The galls are "semicircular in outline, sessile" (transected by the leaf blade and equally developed on both sides of the leaf). An additional female was examined from Massachusetts.

  Nematus inquilinus

  Valid name. — Eupontania salicisdesmodiodes (Walsh) (= Nematus inquilinus Walsh). 

  Notes. — This species was placed in synonymy with Nematus salicisdesmodioides Walsh (Marlatt 1896) and was listed as "unplaced" by Smith (1979). The type material was reared from galls on Salix humilis, the host plant of Eupontania salicisdesmodioides. To fix the usage of this name we designate the lectotype of Nematus salicisdesmodioides as neotype of Nematus inquilinus Walsh. 


externallink: https://www.biodiversitylibrary.org/page/16172889#page/515/mode/1up
description:
  Eupontania salicispisum, new combination. 

  Nematus salicispisum

  Valid name. — Eupontania salicispisum (Walsh), new combination. 

  Host. — Salix discolor: The gall is illustrated by Zinovjev and Smith (1999: fig. 1). They are small, rounded, and attached to the sideveins, with a very small scar visible from the upperside and concave below the leaf surface. 

  Nematus quercicola 

  Valid name. — Eupontania salicispisum (Walsh) (= Nematus quercicola Walsh). 

  Notes. — Nematus quercicola was treated as a synonym of the preceding species by Marlatt (1896), or by others (e.g.. Smith 1979) as a nomen nudum because the only character mentioned by Walsh to distin- guish it from the preceding species was that "all N. s. pisum went underground to pupize" and 'N. quercicola pupized in the gall." A biological feature such as this, by formal reasons, could be treated as a "character," and we should accept this name as an available one. According to Walsh, this species "cannot be distinguished from the gallmaking N. s. pisum male, female." 


externallink: https://www.biodiversitylibrary.org/page/16172767#page/383/mode/1up
description:
  Pontania proxima

  Pontania daedala, n. syn.

  Type locality. — Ithaca, New York. 

  Valid name. — Pontania proxima (Serville 1823) (= P. daedala MacGillivray), n. syn. 

  Notes. — The remnants of host-plant leaves in the vial (M-92) de- posited in the USNM cannot be identified to species, but the sawfly is undoubtedly P. proxima. 


externallink: https://www.biodiversitylibrary.org/page/16172767#page/386/mode/1up
description:
  Eupontania gracilis

  Pontania demissa, n. syn.

  Type locality. — Ithaca, New York. 

  Valid name. — Eupontania gracilis (Mar- latt 1896) (= Pontania demissa Mac- Gillivray), n. syn. 

  Notes. — Larvae and galls were described by Yuasa (1922) as P. demissa MacGillivray 1921 (Y- 191- 1-1). We have not seen larval material with this number. Pontania demissa could be treated either as synonym of Eupontania gracilis (Marlatt 1896) or E. petiolaridis (Rohwer 1917). Both these species are associated with different willow species: Salix sericea Marsh., and Salix petiolaris Smith, respectively. These sawflies are very similar, and they might prove to be conspecific. Both willow species occur in the vicinity of Ithaca, and, at least in herbarium material studied by AGZ, the galls are known also from both host plants. However, Salix sericea seem to be more common there and galls only on this willow were found in the fall of 1997 around Ithaca by AGZ and T Carr. The type of Pontania demissa fits best the type material of E. gracilis, and we consider them as synonymous.


description:
  Euura exiguae, n. sp.

  [Photos of many examples of this gall appear in Figure 31, page 15 of the pdf]

  Gall--Exiguoid-type, thin walled, tapering at both ends, outline sinuate or linear, 20-70 mm long X 5-15 mm wide; surface smooth, pubescent or glabrous, but never glaucous; mature gall uniform brown to russet with exit hole plugged with frass made by mature larva before pupating; 1-4 larvae/gall; willow a silvery, racemose shrub usually under 2 m in sandy soil in or along watercourses. 

  Host.—Salix exiguae Nuttall including ssp. exigua, melanopsis (Nuttall) Cronquist, and synonyms sessilifolia Nuttall (of Jepson 1951, not Cronquist 1964) and hindsiana Bentham; apparently not including ssp. interior (Rowlee) Cronquist, east of Rocky Mountains. 

  Range.—With the willow at least north of Transverse Ranges up to 750m, probably eastward throughout (Treat Basin to Rocky Mountains up to 2300 m. 

  Remarks.—Emergence and oviposition, early March through April, both peaking in late March. Euura exiguae is the commonest sawfly in California and is extremely abundant locally on river sandbars and banks. The species of Euura on S exigua in the Great Basin is probably the same as E. exiguae, but its ocellar basin is often similar to E. lemmoniae, and the sheath is rougher in outline than that of individuals from cismontane California. 


description:
  Euura geyerianae, n. sp.

  [Photos of many examples of this gall appear in Figure 32, page 15 of the pdf]

  GALL. — Exiguoid-type (Fig. 32); thick walled, shape bulbous, surface smooth, glabrous, undulating; young galls very blue-white glaucous, mature glossy green to mottled red and brown, occasionally glaucous; size 7-15 mm long X 5-10 mm wide; exit hole made by larva before pupating; willow a clustering, glaucous-branched shrub usually under 4 m in wet sites from lodgepole pine forest (in California) down to juniper-pinyon sagebrush woodland (in Oregon). 

  Host.—Salix geyeriana Andersson. 

  Range.—Adults reared only from type-locality in southern Oregon. Rare galls seen at Hobart Mills, Nevada County, California (elev. 1797 m) along Prosser Creek east of the Sierra Nevada crest


description:
  Euura breweriae, n. sp.

  [Photos of many examples of this gall appear in Figure 34, page 16 of the pdf]

  GALL.—Lasiolepoid-type (Fig. 34); thin walled, elongate, irregular in shape, 20-40 mm long X 5-15 mm wide; color vivid yellow-green tinged with red; immature galls very pubescent, pale green; mature galls shiny; 1-3 larvae/gall. 

  Host.—Salix breweri Bebb. 

  Range.—Inner California Coast Ranges presumably with the willow, 50-300 m; sawfly collected only from Putah Creek basin, southwest Yolo and adjacent Napa Counties, 50-75 km west of Sacramento. 

  Remarks. — Emergence and oviposition April to early May. The host range is poorly known; S. breweri is a clustering serpentine endemic within stream beds in the Chaparral of the inner California coast ranges, 0.5-3 m tall, the dominant willow along the main tributaries of the upper Putah Creek basin. 


description:
  Euura scoulerianae, n. sp.

  [Photos of many examples of this gall appear in Figure 33, page 16 of the pdf]

  GALL. — Exiguoid-type (Fig. 33); thick walled, shape elongate, irregular, usually tapering apically, 20-40 mm long X 5-15 mm wide, surface smooth, occasionally pubescent, but usually shiny; young gall dark green with red mottlings which usually turn brown on mature galls; exit hole cut by mature larva and plugged with frass before pupating; gall often dried hard and colored gray by spring; host willow a clustering shrub or small tree, usually under 4 m, with pungent foliage, even when dried; willow usually on very dry elevations (for a willow) in yellow pine-red fir and lodgepole pine forests. 

  Host.—Salix scouleriana Barratt. 

  Range.—With the willow in the Sierra Nevada and adjacent ranges from Mt. Shasta southward, between 1300 and 2100 m. 

  Remarks.—Emergence and oviposition from early May to mid June, with cocooning in late September. This is a sympatric sibling species with E. lemmoniae and E. lasiolepis. The scarcity of paratypes results from late recognition of the species (1967) and the consistently high level of parasitism (rarely below 75%) throughout its range.


description:
  Euura lemmoniae, n. sp.

  [Photos of many examples of this gall appear in Figure 36, page 16 of the pdf]

  GALL.—Lasiolepoid-type (Fig. 36); very similar to that of E. lasiolepis but usually smaller (10-60 mm X 6-15 mm) and more globose; surface usually striate, matte; color dark green to red-brown; willow a clustering shrub usually under 3 m tall, (rarely to 5 m) on boggy sites from upper yellow pine forest to upper lodgepole pine forest. 

  Host.—Salix lemmonii Bebb. 

  Range.—With the willow in the Sierra Nevada and adjacent ranges from Mount Lassen south, between 1500 and 2800 m, principally 2100-2500 m. The lower elevations are all in cold alpine meadows in the north-central Sierra Nevada, and equivalent to higher altitudes elsewhere. 

  Remarks.—Emergence and oviposition late April to mid June, peaking in late May; very abundant in alpine meadows, attaining enormous populations locally; see comment in discussion of speciation in stem-galling Euura.


description:
  Euura lasiolepis n. sp.

  [Photos of many examples of this gall appear in Figure 35, page 16 of the pdf]

  GALL.—Lasiolepoid-type (Fig. 35); thick walled, tortuous; surface smooth, shiny, or corrugated; color yellow-green except purple to red in bright sun; 20-70 mm long X 3-21 mm wide; 1-5 larvae/gall; willow a shrub or small tree usually under 5 m, but to 10 m in wet sites. 

  Host.—Salix lasiolepis Bentham. 

  Range.—With the willow at least from Monterey County north to Mendocino County, California, and from the coast to the west face of the Sierra Nevada (but see subsequent discussion). 

  Remarks.—Emergence and oviposition from late February to early June, peaking in early March; coast and valley populations with cocooning from October through February. Locally very abundant on susceptible willow clones along roadside ditches and sloughs, and marshy areas along foothill streams. East of the Sierra Nevada Divide from 1225—1825 m is a black Euura on S. lasiolepis, average saw L:W = 17.5:1, dimensions 1.56 mm X 0.09 mm, body slightly paler and smaller than coastal (black) phase. For status of this, another form on 3". rigida, and sibling species on S. scouleriana, see discussion of speciation in stem-galling Euura. 


description:
  [Euura sp., petiole and midrib galls on S lasiandra]

  [Photos of many examples of this gall appear in Figure 30, page 15 of the pdf]


description:
  [Euura sp. bud gall on Salix lemmonii]

  [Photos of many examples of this gall appear in Figure 29, page 15 of the pdf]


description:
  a gall, similar to the one made by P. proxima, is made by a species on the native S. lasiandra in the Sierra Nevada and adjacent ranges at elevations of 1660-2200 m, and it is unlikely that it will prove to be P. proxima.

  [A photo of these galls appears in Figure 5A, page 6 of the pdf]


description:
  Pontania proxima [Russo makes no distinction between [Pontania proxima](https://www.gallformers.org/gall/3629) and the species mentioned by Smith. They are assumed to be distinct because Smith speculates this is the case and because no US native willows, including Salix lasiandra, are listed as hosts of Euura proxima by Liston et al 2017]
  Bean-gall sawfly
  [Page 223]

  Hosts: Salix lasiandra (S. lucida subsp. lasiandra)

  Galls protrude equally on both sides of host leaves and are smooth, glabrous, and red on top and yellow-green underneath. 


description:
  Salix lasiandra is the only host Russo 2021 lists for Pontania proxima. Because this species is not listed as a host by Liston et al 2017 and because Smith's original mention speculates it is likely not the same species, we treat [the similar gall on S lasiandra](https://www.gallformers.org/gall/3656) as a distinct and undescribed gall.


externallink: https://babel.hathitrust.org/cgi/pt?id=wu.89041294323&view=1up&seq=71&skin=2021
description:
  Pontania hyalina

  Salix [Salix exigua added as a placeholder]
  Leaf galls

  Ovate, reddish gall in rows on either side of midrib, length .25 to .375 inch, sawfly, spring


description:
  Euura atra

  Pteronus ater
  Cryptocampus ater
  Nematus ater
  Nematus angustus
  Euura angusta
  Cryptocampus angustus
  Euura salicicola
  Cryptocampus helveticus
  Euura nigra

  Hosts: Salix alba, fragilis

  This species usually does not form galls: larvae simply tunnel along the shoots, for a short distance

  Range: Introduced to North America


description:
  Pontania with Type II galls [Smith does not name or describe a species and is ambiguous about whether he considers these host varieties or distinct species on each host.]

  [A cross sectional drawing appears in Figure 4, on page 5 of the pdf]

  Pontania with Type II galls are confined to the exiguoid willows (in California, S exigua and varieties, and S. geyeriana Andersson). These cecidia are large (9-12 mm), round, thin-walled, have a slightly wrinkled surface, and protrude through both upper and lower surfaces of the leaf. They do not fit any of Benson's categories. S. geyeriana is very pruinose (covered with a white, waxy bloom), and so is the gall. The unidentified Pontania is a robust amber and brown species. Since S. exigua is not pruinose, neither is the gall. The Pontania on it is entirely black. These 2 willows are sympatric in transmontane California (i.e., that portion of California east of the Sierra Nevada Crest) from 1200 to 2100 m, and so are the sawflies.


description:
  According to Smith's photos and Russo's drawings, Euura lasiolepis forms narrow, tapered stem galls. However, abrupt, potato-like galls have also been observed on Salix lasiolepis. These may be induced by a distinct species, though Smith speculates that "it is very unlikely more than a single [Euura] species attacks 1 species of willow." Smith also states that the stem gallers on his "lasiolepoid willows" are "virtually identical structurally," further suggesting that the morphological differences between Euura lasiolepis and its sister species Euura lemmoniae are not diagnostic in the absence of a host ID and likely do not indicate distinct morphological species on either host. In his 1970 paper Smith notes that the lasiolepis-group stem gallers form galls that are "usually more bulbous than those of the exiguae group."


description:
  Pontania with Type III galls [Smith does not name or describe a species and is ambiguous about whether he considers these host varieties or distinct species on each host.]

  [A cross sectional drawing appears in Figure 4, on page 5 of the pdf]

  Type III galls are attached to the S. myrtillifolia Andersson-glauca L.-phylicifolia L. complexes, and apparently equivalent to part of the P. vesicator (Bremi) group of Benson. The gall is large and oval (10 mm), and protrudes through both leaf surfaces from the midrib. It has slightly irregular, moderately thick walls, and a smooth surface which may be lightly pilose in those incited on the S. myrtillifolia and S. glauca complexes, or shiny and glabrous when on the S phylicifolia complex.


description:
  Pontania with Type IV galls [Smith does not name or describe a species and is ambiguous about whether he considers these host varieties or distinct species on each host.]

  [A cross sectional drawing appears in Figure 4, on page 5 of the pdf. Two photos appear on page 7, Figure 6.]

  Type IV is on the S. lasiolepis group, and is a small (5 mm) thin-walled variety, probably equivalent to part of Benson's P. viminalis (L.) group. The gall hangs from the under surface of the leaf midrib, and is smooth and glossy (Fig. 6 A). The gall may be conical or ovoid on the long axis. The Pontania of this group making galls on S. lemmonii and relatives and on S. rigida [cordata?] tend toward having spherical cecidia, while those on S. scouleriana Barratt are usually conical (Fig. 6 B). All are montane, although the one on S. rigida ranges throughout the Great Basin.


description:
  Pontania with Type V galls [Smith does not name or describe a species and is ambiguous about whether he considers these host varieties or distinct species on each host.]

  [A cross sectional drawing appears in Figure 4, on page 5 of the pdf]

  Type V Pontania galls are on the S. lasiolepis group also, and are large (10 mm) and thick-walled. They come closest to some in Benson's P. viminalis group. The galls hang from the under surface of the leaf midrib and are round, smooth-surfaced, and usually on a short pedicel. There are 2 species of Pontania known from the far west with galls of this type. An amber one on S. rigida [cordata?] in the Great Basin makes a cecidium with a glossy surface, and a black species makes galls with pruinose surfaces on S. sp. near lemmonii in central Oregon.


description:
  Pontania with Type VI galls [Smith does not name or describe a species and is ambiguous about whether he considers these host varieties or distinct species on each host.]

  [A cross sectional drawing appears in Figure 4, on page 5 of the pdf]

  Type VI is the most common Pontania gall-form in California. It is large (10 mm), thick-walled, and protrudes through both upper and lower leaf surfaces. The galls may be round or oval, and the surface is smooth (or pubescent, if the host is so) except for characteristic warty lenticels. Adjacent cecidia frequently anastamose. This category comes close also to the P. viminalis group. On S. sp. near lemmonii in extreme northern California, Type VI galls are pruinose (host plant effect), but nearly all others of Type VI are glossy or lightly pubescent. The most common Pontania in California makes galls that belong to this group, and has been known traditionally as P. pacifica Marlatt. The actual identity of this polymorphic species is unclear, and it is probably synonymous with [P. californica Marlatt](https://www.gallformers.org/gall/3539) and others described by him in his 1896 paper. The species attacks S. lasiolepis, especially variety bigelovii Torrey, and the center of distribution is from Monterey County north through Marin County along the California coast. There is another species of Pontania on transmontane S. lasiolepis. Other Pontania making Type VI galls include the very common species on S. lemmonii and Salix sp. near lemmonii, and a rare one on S. scouleriana. Both are common throughout the Sierra Nevada and in the southern Cascade Range. 


description:
  The Pontania on S. sitchensis Sanson ranges throughout the Sierras and Cascades, and resembles [Type VI](https://www.gallformers.org/gall/3662) except for a lack of stomata (Fig. 5 B) [see page 6 of the pdf for figure].


description:
  A Pontania on the California-endemic S. breweri Bebb makes rather pilose galls which have relatively thin, irregular walls with occasional lenticels, and the cecidia may anastamose.


description:
  The petiole gall-makers (subgenus Euura, in part) are the next most specialized. Six species of Salix in all groups are attacked in California, but exactly how many species of sawflies are involved is not known. All but one are smaller (females are 5 mm or under) than either the stem or bud-gallers. Petiole-galling Euura pupate in the soil as do the Euura {Gemmura). By far the most common species of this type is the exceptionally large (8 mm) one on S lasiandra (Fig. 7 B). It is widespread from sea level along the Pacific Coast to above 2000 m in the Sierra Nevada. The gall is up to 40x20 mm, and may be on petioles, midribs, or both. Infestations are massive, and a single tree may have most leaves with several galls. Up to 4 pale green larvae may inhabit a single gall, and parasites rarely destroy all of them. Late instar larvae may cut holes in the walls of the gall and clean house as do P. proxima. The purple-gray last stage larvae depart over a period of 2 or 3 weeks from each gall. The presence of the petiole gall apparently inhibits abcisin formation, since infested leaves may remain on the branches until blown off or decayed. Montane and littoral specimens of petiole galling Euura on S. lasiandra appear to be the same species, but series are difficult to obtain, abundance of galls notwithstanding. While other petiole gall-makers present the same rearing problems as do the Gemmura, and are usually even less common, the Euura on S. lasiandra seems to have some peculiar diapause-breaking requirement. One can rear hundreds to the prepupa and never get an adult.


description:
  [This entry is a placeholder for petiole galls on any Salix species in the West that is apparently neither the one Russo lists on [Salix lasiandra](https://www.gallformers.org/gall/3625) or the one he lists on [Salix barclayi](https://www.gallformers.org/gall/3626).]

  The petiole gall-makers (subgenus Euura, in part) are the next most specialized. Six species of Salix in all groups are attacked in California, but exactly how many species of sawflies are involved is not known. 

  The next most common petiole-galler in the far west is a tiny (under 5 mm) species on transmontane S. Exigua in the Great Basin. Occasional petiole galls of other species are found on S. lasiolepis, S. Iemmonii, S. sp. near lemmonii, and S. geyeriana. 


description:
  Pontania pacifica

  P pacifica is limited to S. lasiolepis as its food plant.

  The galls incited by P. pacifica are quite variable in size, shape, color, and number per leaf. They are found at either or both sides of the midrib in the leaves of Salix lasiolepis. When fully developed they are spherical, oval, or bean-shaped (Fig. 1), as much developed on the upper as on the lower surfaces of the leaf, although specimens much more developed on the lower surface are commonly found, particularly on leaves of fast-growing suckers, some of which have the upper surface only slightly raised above the lamina. Galls with the upper surface more developed than the lower have never been found. The cuticle is smooth, shiny. The color is red, pink, or reddish brown on the upper surface, and green or greenish yellow on the lower; not uncommon are those that are red on both sides, or entirely green. Apparently the development of the red pigment is related to the amount of light received by the gall; the green ones are frequently found on leaves that are in the shadow. The average size is 8.4 mm in the longest dimension (average from 50 galls), ranging from 7 to 11 mm. Most of the galls occur singly or in pairs, one on each side of the midrib, but any number up to 14 galls per leaf has been observed. The higher numbers occur more frequently in late summer (Fig. 2).


externallink: https://www.biodiversitylibrary.org/page/3830881#page/264/mode/1up
description:
  Euura salicis nodus, n. sp.

  On S. longifolia [interior]

  A mere gradual enlargement of a twig from 1/4 more than its norma] diameter up to twice its normal diameter, almost always without any abnormal roughness on the external bark, and always not confined to one side only of the twig. General color that of the twig. When cut into, Aug. 28, the interior of each gall is found to be pithy, and to contain 1 — 3 larvae in separate cells. Frequently, on a piece of a twig 6 inches long, 2, 3 or 4 of these galls are placed at irregular intervals. No appearance internally of any transverse plates or transverse fibres as in S. ovum and S. ovulum. Length .75 — 1.50 inch; diameter .10 — .2.5 inch. Described from 31 affected twigs. Abundant but very local. Very like the Cecidomyidous gall S. nodulus on the same willow, but is much larger, is polythalamous instead of monothalamous, and occurs near Rock Island, IL., in quite a different locality. Analogous willow-galls are made in Europe, not by a Euura, but by several small species of Nematus.


description:
  An ovate globular swelling from midrib to leaf edge on Salix traceyi. The surface is hairless and spotted with small white lenticels. Observed in Oregon in July. Conforms to Smith's [Type VI leaf gall](https://www.gallformers.org/gall/3662). 


description:
  Large, thick-walled swellings on leaves of Salix prolixa. The galls are green but spotted with darkened lenticels. Observed in September in Oregon.


description:
  Unknown #4
  Peach-gall sawfly
  [Page 224; plate 377]

  Hosts: Sierra willow (Salix cf eastwoodiae)

  This sawfly induces monothalamous, round to oblong, fuzzy midrib galls resembling a peach that terminate in a slight projection or tip.

  Adult sawflies have been reared from these galls but have yet to be identified.


description:
  A large, hairless, thick-walled, yellow-green, globular gall predominantly on the lower side of a leaf of Salix lasiandra, between the edge and midrib. Observed in Montana in July. Conforms to Smith's [Type VI](https://www.gallformers.org/gall/3662) leaf gall in structure, but is not on the host group he lists for that type. 


externallink: https://www.biodiversitylibrary.org/page/52142981#page/123/mode/1up
description:
  Pontania monile, new species

  Gall. — Gall occurring on the leaves of willow. Collected at the mouth of the American Fork Canon, Utah, by Mr. E. A. Schwarz, June 29, 1891. 

  Smooth, globular, fleshy galls, 6 to 8 mm. in diameter, occurring from 2 to together in a row on the underside of the midrib of willow leaf. The area of attachment is about one-half the greatest diameter of the gall, and on the upper side of the leaf appears as a slight convexity. When closely placed, the galls lose somewhat of the spherical shape, but rarely grow together. The larva begins eating out the interior of the gall near the base, and is rather robust, 10 mm. in length, with light, resinous head and dark eye-spots; light, yellowish- white body. 

  An exactly similar gall, except occurring 1 or 2 together, is represented in the collection, bearing the label January 10, 1884, without locality. It was collected in a later stage of development, and the interior is completely excavated. In most cases the larva had abandoned the gall, issuing near the base. The specimens probably came from the Northwest. A gall similar to the last was also received from Mr. Lawrence Bruner, Robinson's Ranch, Wyoming, collected September 15, 1881, with the statement that it occurred on the leaves of Populus angustifolia. Examination of the leaves seems to indicate that they are willow rather than poplar, and the gall may be doubtfully referred to the type described above.


externallink: https://www.biodiversitylibrary.org/page/52142981#page/106/mode/1up
description:
  Pontania parva

  Nematus parvus

  Gall. — Length 8 mm.; breadth 6 mm. Of type of desmodioides, but rather smaller and projecting most on lower surface of leaf. In the specimen examined, two occur on the leaf, one on either side of the midrib, and each extends from the latter to the margin of the leaf. Surface, especially lower, tuberculate and rosy. Exit hole of adult on lower side, just at surface of leaf and at end next to petiole. 

  Ten females. — Nevada 4, California 3, Oregon 2, and Arizona and Montana 1 each. (Coll. Am. Ent. Soc.) Also one specimen collected by T. Kincaid at Olympia, Wash. (Coll. Cornell Univ.) One male from California. (Coll. Am. Ent. Soc.) Galls on willow leaf collected by Mr. Ehrhorn, Mountain View, Cal. Two adults reared, which, with galls, are in collection of William H. Ashmead.


externallink: https://www.biodiversitylibrary.org/page/52142981#page/110/mode/1up
description:
  Pontania resinicola, new species

  Gall. — (Frontispiece, fig. 1.) On leaves of Salix californica [eastwoodiae] collected by Albert Koebele at Donner, Placer County, Cal., September 5, 1885. The galls occur in clusters of two to eight on the basal portion of the leaf, beginning usually at the very apex of the petiole. They are commonly paired — if but two, one on either side, or two or four on a side, as the case may be — occasionally occurring singly. In general size and appearance the individual galls resemble those of desmodioides, but are rather more robust or globular, projecting equally on both sides of the leaf and occupying the leaf entirely from the midrib to the edge. Where two or more occur together, they are merged into each other, forming a com- pound gall. In color they are red or pink on the upper side and light yellowish green on the lower. The larva is large and rather robust, indicating a fairly good-sized insect. I have doubtfully referred the gall to Pontania resinicola, the largest Californian representative of the genus, although the galls from which the adults were reared by Mr. Koebele were not saved by him and the ones sent to Washington yielded only an ichneumonid parasite (Bassus euurae) and a tortricid.


externallink: https://www.biodiversitylibrary.org/page/52142981#page/114/mode/1up
description:
  Pontania pisum

  Nematus salicis pisum
  Nematus quercicola
  Nematus pisum

  "Gall. — The gall made by it is found on Salix discolor. A subspherical, pea-like, hollow, pale yellowish-green gall, always growing on the underside of the leaf and almost always from one of the side veins (in one case from the midrib), and attached to the leaf by only a minute portion of its surface; 0.18 to 0.28 inch in diameter, and a few, immature, only 0.08 inch in diameter. Almost invariably there is but one gall to the leaf, but on four leaves there were two, and occasionally two are confluent. Surface in some smooth and even, without pubescence; in others a little shriveled, generally studded in the medium-sized ones with four to twelve small, robustly conical nipples, which in the larger ones have burst into a scabrous blown scar. Only in three out of sixty-two was there any rosy cheek, as in S. pomum. The point of attachment is marked on the upper side of the leaf by a brown subhemispherical depression.

  Range: IL, NY


externallink: https://www.biodiversitylibrary.org/page/52142981#page/115/mode/1up
description:
  Pontania bruneri, new species

  Gall. — (Frontispiece, fig. 7.) Galls occurring singly on the edges of the leaves of Salix longifolia [exigua], having the form and general characteristics of the gall of P. desmodioides. Length from 7 to 10 mm.; smooth, fleshy gall, extending from the midrib considerably beyond the narrow, linear leaf, with a prominent and distinct suture indicating what was the edge of the leaf; in color yellowish, inclined to reddish. Three females, reared from galls collected by Lawrence Bruner on Robinson's ranch, Wyoming, September 15, 1881. The galls at this time were mostly abandoned, only six of them still containing larvae. Adults issued between February 18 and March 3, 1882. (Coll. U. S. Nat. Mus.)


description:
  Numerous small red-orange circular leaf spots on a leaf of Salix candida, glossy above and hairy like the surrounding leaf below but not protruding on either side. Observed in Montana in July. 


externallink: https://www.biodiversitylibrary.org/page/52142981#page/116/mode/1up
description:
  Pontania pomum

  Nematus salicis pomum
  Nematus hospes
  Pontania hospes

  Gall. — (Frontispiece, fig. 4.) The gall S. pomum found on Salix cordata [per Zinovjev, this is eriocephala] and very rarely on S. discolor. A smooth, fleshy, sessile, globular, or slightly oval monothalamous gall, like a miniature apple, 0.30 to 0.55 inch diameter, growing on one side of the midrib of a leaf, and extending to its edge or beyond it. The principal part of the gall projects from the under side of the leaf; very rarely it is bisected by the leaf. Color greenish yellow, sometimes with a rosy cheek, especially the upper surface, and often with little dots. Fully mature July 31. An analogous gall is formed in Europe on various willows by Nematus gallicola Westw.

  Range: IL


externallink: https://www.biodiversitylibrary.org/page/52142981#page/117/mode/1up
description:
  Pontania hyalina

  Messa hyalina

  Gall. — (Frontispiece, fig 2.) Fleshy galls, occurring in two parallel rows, one on either side of the midrib, sometimes touching but not originating from the latter, and rarely extending to the edge of the leaf; sometimes as many as twenty on a single leaf; in other cases confined to a row on one side of the leaf, or occasionally occurring singly; shape irregular, elongate-ovate, projecting equally on both surfaces of the leaf; length 7 to 10 mm., the abortive ones smaller. Color on upper side more or less brownish red; beneath white, with slight purplish tinge. The galls result from the punctures of the females in the very tenderest leaves, the wound closing and becoming invisible. The eggs and larvae are subject to the attacks of mites, Thrips, a curculionid (Anthonomus sycophanta Walsh), and a lepidopterous larva which eats out the entire interior of the gall, tenthredinid larva and all.

  Many specimens. New Hampshire, New York, Massachusetts, Pennsylvania, New Jersey, and Canada. (Colls. Am. Ent. Soc. and U. S. Nat. Mus.) 

  Galls: Boscawen, N. H., C. V. Riley, collector, July 16-25, 1883, "on Salix fragilis, a large tree, 50 to 70 feet high, with a rough bark and trunk, smooth branches, and galls very plentiful on younger leaves all over the tree." The adults were obtained between April 29 and May 21, 1881 ; also chalcidid and other parasites. 

  Magnolia, Mass., July 10, 1883; gallmaker not reared. Hymenopterous parasites issued July 20, 1883. 

  Richfield Springs, N. Y., Theo. Pergande, collector, February 8, 1880; adults issued March 3 to April 21, 1887; also chalcidid parasites and a dipterous guest fly. 

  Pittsburg, Pa., J. C. Leach, collector, July 25, 1891. 

  Pointe au Pic, Quebec, Canada, E. Corning, collector, August 28,1891.


externallink: https://www.biodiversitylibrary.org/page/52142981#page/118/mode/1up
description:
  Pontania californica, new species

  Gall. — Gall of the type desmodioides, not differing in the dried specimens in any noticeable manner from the latter. Length 8 to 12 mm. Normally but one gall occurs on a leaf. The galls were received from Mr. H. T. Turner, Eastlake, Cal., August 26, 1883, and the adults issued between September 18, 1883, and March 24, 1884. 

  Nine females and 3 males, 8 of which — 6 females and 2 males — were reared from willow-leaf galls collected by Mr. Turner in California. (Coll. U. S. Nat, Mus.) 

  One male collected at Alameda, Cal., in March by Mr. Koebele, and the others collected in Southern California, (Colls. U. S. Nat, Mus. and Am. Ent. Soc.)


externallink: https://www.biodiversitylibrary.org/page/52142981#page/119/mode/1up
description:
  Pontania gracilis, new species

  Gall. Galls somewhat similar to desmodioides, but much more robust, nearly spherical, extending from midrib to considerably beyond edge of leaf; diameter 9 to 13 mm.; surface smooth. 

  Galls collected in Virginia by Mr. Pergande September 29, 1885; adults issued April 19 and 29, 1886. 

  Two females. Virginia. (Coll. U. S. Nat. Mus.)


externallink: https://www.biodiversitylibrary.org/page/52142981#page/120/mode/1up
description:
  Pontania desmodioides

  Nematus salicis desmodioides
  Nematus inquilinus

  Gall. — The gall is found on S. humilis. It is smooth, flattish, fleshy, sessile, yellowish green, monothalamous, semicircular in general shape like the seed of a Desmodium or the quarter of an orange. It is about equally divided between the two surfaces of the leaf; no rosy cheek. Generally there is but one gall on a leaf; one leaf was seen with three upon it. Length 0.23 to 0.50 inch. One hundred and thirty-one specimens. Gall mature July 30. 

  Galls probably belonging to this species have been received from the following localities: Lafayette, Ind., F. M. Webster, August 15, 1890, from which were obtained two parasites, Sympiesis sp. and Murytoma studiosa Say, supposed to be parasitic on Anthonomus sycophanta Walsh ; Eichfield Springs, N. Y., Th. Pergande, collector, September 28, 1886. Cadet, Mo., J. G. Barlow, collector, September 24, 1890. 


externallink: https://www.biodiversitylibrary.org/page/52142981#page/123/mode/1up
description:
  Pontania pyriformis new species

  Gall. —Galls occurring on leaves of Salix californica(?) [eastwoodiae]. Collected by Albert Koebele, Donner, Placer County, Cal., September 5, 1885. Galls occur on the underside of the leaf, attached to or near the midrib, usually singly, but sometimes two separately on the leaf, or more frequently partly coalescing, in which case one is usually abortive. They are pear shaped, attached rather broadly (1/4 to 1/2 greatest diameter) at the larger end, and rather acutely pointed, sometimes slightly curved at tip, or more rarely bifurcate. They consist of a mere shell, containing with the larva very little frass, as though the larva had subsisted more on secretions than on the solid interior of the gall — the gall giving now no indication of ever having been fleshy and solid. The full-grown larva escapes through the base of the gall at its point of attachment, emerging, therefore, on the upper side of the leaf. The larva is white, with light-brown head and black eye-spots, 7 to 8 mm. long. Six specimens of Pimpla euurae Ashm. were reared, but no gall-flies.


externallink: https://www.biodiversitylibrary.org/item/99818#page/13/mode/1up
description:
  Eriophyes sp.
  Chadwick's No. 65 

  Host Fagus grandifolia Ehrh. 

  This gall occurs on the under side of the leaves of the host plant. It is an erineum, white and frost-like at first, turning to a brown colour at a later stage. The anatomical structure of the interior of the leaf remains perfectly normal, the effect of the stimulation being confined to the epidermis. This produces a large number of unicellular, capitate hairs, resembling miniature mushrooms, the resemblance to which is the more striking since the stalks of the hairs are bulbous at the base, as shown in Fig. 3. The hairs on the normal leaf are long, acicular and unicellular. As this gall is produced with no increase in the number of cells in the leaf, anatomically it stands as a simple type of "hypertrophy", the remaining forms all exhibit the more advanced phenomenon of cell proliferation.


externallink: https://www.biodiversitylibrary.org/item/99818#page/13/mode/1up
description:
  Eriophyes querci (Garman). 
  Chadwick's No. 112 

  Host Quercus macrocarpa Michx. 

  In this gall, which is of the "dimple" type, the depression is on the under and the elevation on the upper side of the leaf. The hollow is filled with a dense mass of brown pubescence. In rare cases the elevation is on the under side of the leaf, when the pubescence then covers it. 

  The leaf blade in this case has become of nearly twice the normal thickness. This has resulted from cell division which has occurred in the tissues of both the palisade and the spongy parenchyma, producing a compact mass of undifferentiated cells, entirely without intervening air spaces. This tissue is shown in Fig. 6.

  The epidermis has responded to the stimulation by producing many long, acicular, unicellular hairs, which are narrowed at the base. The hairs are stellate on the normal leaf of the host, but are simple, uni- cellular and acicular on its reproductive axis. The same feature is true of Quercus robur var. pedunculate, and in all probability of the other oaks. This appears to be a clear case, not of the production of a new type of trichome, but of a reversion.


externallink: https://www.biodiversitylibrary.org/item/99818#page/14/mode/1up
description:
  Eriophyes Sp. 
  Chadwick's No. 2

  Host Acer negundo L. 

  A shallow dimple on the under side of the leaf, filled with a white pubescence. In this gall as in the preceding species, the leaf blade has been very much thickened by proliferation in the mesophyll. The cells produced are circular in outline and of about the same size as those of the normal spongy parenchyma. The hairs produced in this case not infrequently consist of from 2 to 3 cells which are very much convoluted. They are well shown in Fig. 4. The hairs on the normal leaf of the host are straight or only very slightly curved, but the glandular, convoluted type of hair is found on the inflorescence. Both the normal and abnormal hairs are composed of the same number of cells.


externallink: https://www.biodiversitylibrary.org/item/99818#page/14/mode/1up
description:
  Eriophyes Sp. 
  Chadwick's No. 84 

  Host Populus grandidentata Michx. 

  A deep dimple gall with the convex part on the upper surface of the leaf. The gall is light green above, with the contents of the depression dark red. 

  The cells produced by the palisade parenchyma can be distinguished in this case from those arising from the spongy parenchyma. The former are almost square in outline and placed in two very regular rows immediately below the upper epidermis, and parallel with it. This tissue can be seen in Fig. 2. The latter constitute a tissue made up of cells which are circular to elliptical in outline. These cells are much smaller than those produced by the palisade layer. The outgrowths from the lower epidermis described in various ways as trichomes, granules, etc., are in reality produced by a complicated folding, in which only the lower epidermis and the spongy parenchyma participate, as shown in Fig. 2. 

  A cross section of the gall shows a number of vascular strands, but in my opinion the gall-producing stimulus only enlarges the veins that are already present in the normal leaf; it does not originate a special vascular system for the gall. 

   Eriophyes Sp. 
  Chadwick's No. 88. 

  Chadwick considers this form, first described by Jarvis, the same as his No. 87. But the latter is characterized by a depression on the under side of the leaf, the former by an elevation, so that the two are constantly distinct. 

  Host Populus tremuloides Michx. 

  A dimple gall with the elevation on the under surface of the leaf. The elevation is a lighter green than the surrounding normal leaf and the folds that occupy the concavity are greenish-yellow or reddish in colour. 

  In dealing with the anatomical structure it is to be noted that the spongy parenchyma has in this case remained normal. The folds are produced in the same manner as in the preceding species, except that in this form it is the upper epidermis that undergoes the folding process. The nature of this folding can be seen in Fig. 1.


externallink: https://www.biodiversitylibrary.org/item/99818#page/15/mode/1up
description:
  Eriophyes Sp. 
  Chadwick's No. 93. 

  Host Prunus nigra Ait. 

  A very much elongated pouch gall, greenish or whitish in colour, found on the upper side of the leaf with the opening on the under side. 

  All the characteristics of the normal mesophyll have been completely altered in the affected part of the leaf. Its cells, which, with the epidermis, constitute the wall of the gall, are larger than the normal and are elongated parallel to the long axis of the outgrowth. The upper epidermis which forms the epidermis of the gall has not been affected, but the cells of the lower epidermis which line the gall cavity have become much enlarged and in addition have produced a large number of closely set trichomes which project into the gall cavity. The nature of these is shown in the upper part of Fig. 5. These structures are often from 2 to 3 cells in length. Around the opening of the gall a circle of closely set acicular hairs occurs. The hairs on the outside of the gall and on the normal leaf are also of the acicular type. The vascular strands are much larger than those of the normal leaf but appear to be simply the stimulated normal veins.


externallink: https://www.biodiversitylibrary.org/item/99818#page/16/mode/1up
description:
  Eriophyes abnormis (Garman).

  Chadwick's No. 144

  Host Tilia americana L.

   A very much lobed pouch-gall, usually on the upper side of the leaf, found rarely on the under side. The opening which is on the opposite side of the leaf to the pouch is surrounded by a dense growth of acicular trichomes. 

  The anatomical structure of this gall shows it to combine the characteristics of a pouch-gall with a type in which the epidermis lining the larval cavity is thrown into folds, as described in the case of the galls on Populus. The foldings of the lining of the gall cavity often coalesce, and practically divide the cavity into a number of compartments. Morphologically this is one of the most highly differentiated of our Phytoptocecidia. The lining epidermis has produced a large number of acicular, unicellular trichomes; these in some cases almost fill the cavities. The hairs surrounding the gall aperture are of the same type, as are also the normal hairs of the leaf. Glandular cells are much more abundant in the gall tissues than in those of the normal leaf.


externallink: https://www.biodiversitylibrary.org/item/99818#page/16/mode/1up
description:
  Eriophyes serotinca Beut.

  Chadwick's No. 100

  Host Prunus serotina Ehrh.

  This is a club-shaped gall, produced on the upper side of the leaf of the host. The aperture of exit, which is on the lower side, is surrounded by fine white hairs. It varies in length from 5 to 8 mm. and at a distance from the apex of about two-thirds the total length, it is narrowed into a stalk with an average diameter of 1 mm. In color it varies from green to a distinct red. 

  The stimulation has not produced very marked changes in the structure of the leaf near the origin of the gall. Apart from the fact that the spongy parenchyma has divided more actively, the mesophyll is normal. The upper epidermis of the leaf that forms the outer covering of the gall, has its cell walls abnormally thickened. The lower epidermis that lines the gall cavity has larger cells than the unstimulated epidermis, and from these cells originate elongated, unicellular trichomes with bulbous bases. The hairs on the normal leaf are acicular and unicellular. While the cells in the neck of the gall are arranged in rows parallel to its length, the larger cells that form the main body of the gall are not regularly placed. The vascular strands pass up from the leaf at a distance of about three cell layers from the gall cavity.


externallink: https://www.biodiversitylibrary.org/item/99818#page/17/mode/1up
description:
  Aphid Gall (Unclassified), 

  Host Populus balsamifera L. 

  A pouch-like gall on the under surface of the leaf, produced by a fold in the blade near the base of the midrib. One edge of the fold is attached along this midrib. The slit-like opening, which is on the upper surface of the leaf, extends the full length of the gall. This species resembles very closely the gall produced by Cecidomyia majalis Bass. The general structure is shown in Fig. 7.

  Dimensions: — Length along line of attachment to midrib, 10-12 mm. ; Width, 4-5 mm. 

  In the part of the leaf blade that forms the gall all resemblance to the normal mesophyll has disappeared. A compact mass of tissue has taken its place, the cells of which are much larger than normal mesophyll cells. Towards the interior of the gall the cells become smaller and richer in protoplasmic contents. The upper epidermis forming the interior of the gall remains practically normal, except that it produces longer and more abundant trichomes than when unstimulated. These trichomes are usually three cells in length. A cross section of this gall shows two small groups of cells with porous laminated sclerenchymatous walls, one of which is situated near the midrib and the other exactly op- posite on the other side of the gall opening. Thus each side of the gall aperture is bordered by a band of sclerified cells, as shown in the trans- verse section of Fig. 8. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/18/mode/1up
description:
  Hormaphis hamamelidis Fitch.

  Host Hamamelis virginiana L.

  The gall formed by this species is found on the upper side of the leaf of the host, but the larvae escape from an opening on the under side. The mature gall is conoidal in shape with the apex usually slightly bent over. General structure is illustrated in Fig. 12. A circular ring of tissue covered with pubescence surrounds the gall opening which is shown in Fig. 12. 

  Dimensions: — Average length of gall 10.5 mm.; diameter at base 4 mm. 

  The gall is composed of small cells placed close together, forming a compact and very uniform tissue. The cells are arranged with their longer diameters pointing in the direction of the gall apex. In a longi- tudinal section the vascular strands are seen to pass up each side at a depth of about three cells from the gall cavity. The beaks of the larvae, often found imbedded in the wall of the gall, were inserted far enough to almost reach these vascular strands. The hairs that surround the gall aperture are acicular and unicellular. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/18/mode/1up
description:
  Hamamelistes spinosus Shimer. 

  Host Hamamelis virginiana L. 

  The galls in this species are modified flower buds. These are some- what elliptical in outline with gradually tapering stalks. They are covered with spines, which are usually curved. The opening is situated at the union of the stalk and the gall proper. This opening is funnel- shaped and is surrounded by a circular ring of tissue as in the preceding species on the same host. The pubescence is absent in this case.

  Dimensions: — Average length including stalk 21 mm.; average width 10 mm. 

  This gall is covered by an unusually small-celled epidermis. The spines that are so noticeable a feature are found to consist of projections of the epidermis, filled with cells in continuity with the mesophyll. The cells of the gall are almost perfectly circular in outline and packed together very closely. This tissue is very uniform except in the four or five layers adjoining the gall cavity. In that zone the cells are smaller and richer in protoplasmic contents, constituting a fairly well marked nutritive layer.

  In cross section of the gall about thirty main fibro-vascular bundles are cut; these are comparatively large and situated near the larval cavity. Two of these have been cut in the section shown in Fig. 10. Other smaller strands are cut further out. The gall receives all the fibrovascular strands that, under normal conditions, would have passed up into the flower. The interior of both this and the preceding species is almost perfectly glabrous.


externallink: https://www.biodiversitylibrary.org/item/99818#page/19/mode/1up
description:
  Aphid Corrugations on Birch.

  Betula lenta L.
  Betula alba var. papyrifera (Marsh) Spach.

  The primary folds in the leaf that form this gall run parallel to the main veins, with the latter as boundaries between them. Their crests are on the upper side of the leaf, while the hollows which form the larval chambers are on the under side. The primary folds are divided into secondary folds, and these again into depressions resembling minute Acarina dimple-galls. This complex arrangement is conditioned entirely by the veining of the leaf, since each fold, primary or secondary, is sup- ported along its edges by veins. The folding can be seen in Fig. 9. The anatomical characteristics of these galls show that the folding of the leaf has not entirely changed the structure of its normal mesophyll. Around the gall cavities the spongy parenchyma is nearly normal through- out and the palisade layer is recognizable in different places. The cells, however, are considerably larger than the cells of the normal mesophyll. The cells of the lower epidermis, that form the lining of the gall cavities, are well filled with food materials for the larvae. The supporting veins on each side of the fold send out branches that supply the gall with an adequate vascular system. Hormaphis hamamelidis Fitch and Hamamelistes spinosus Shimer, as worked out by Pergande,^° show that they inhabit alternately Betula nigra L. and HamameUs virginiana L. The galls on the birch leaves are produced by the fourth genera- tion of Hamamelistes spinosus Shimer. Pergande described them as "pseudo-galls or corrugations". The witch-hazel galls produced by the stem-mother of this species are plentiful in this locality, but Betula nigra L. is not found here. The Aphids have consequently been compelled to extend their list of food plants to include B. lenta L. and B. alba var. papyrifera Spach.


externallink: https://www.biodiversitylibrary.org/item/99818#page/20/mode/1up
description:
  Pemphigus vagabundus Walsh.

  Host Populus deltoides, Marsh.

  All the leaf rudiments of the terminal bud appear to be concerned in the production of this gall. Yet it is in reality a large pouch-gall with its wall thrown into smaller secondary folds. The apex of the stem, from which the gall originates, is usually swollen to nearly twice its normal diameter. These galls often remain on the host plant until the next season's galls begin to appear. The cells composing this gall form a compact and fairly uniform tissue and a nutritive layer is not clearly differentiated. About one- third of the thickness of the gall wall, on the side next the larval chamber, however, is composed of cells that are somewhat larger than the remaining cells. The epidermal cells, lining the gall cavity, are elongated into short trichome-like structures. The phyllome origin of this gall is revealed by the presence of well defined stomata on its epidermis. These structures are numerous and appear to be quite normal. Glandular cells are plentifully distributed. Vascular strands pass irregularly throughout the wall of the gall.


externallink: https://www.biodiversitylibrary.org/item/99818#page/20/mode/1up
description:
  Pemphigus rhois, Fitch.

  Host Rhus typhina L.

  A balloon-shaped gall with the regularity of its outline destroyed by the elongated lobes that cover its surface. A gall is shown in Fig. 14. The epidermis is slightly pubescent and coloured red, shading into yellow and green. It originates from the under side of the leaf, and the point of attachment on the upper side is indicated by a small papilla covered with a dense pubescence. These galls vary in size from very short types less than i cm. to those that are 4 to 5 cm. in length. composed of the ordinary vascular elements of the normal leaf that have been stimulated to increased activity. There is not a special tracheary system originated for the gall. In the galls the strands occupy a definite position, since in the normal leaf they occupy a definite place in relation to the spongy and the palisade parenchyma. Large glands are present in the gall tissue, as shown in Fig. 14. A gland is found invariably asso- ciated with a fibro-vascular strand and seems to have its counterpart in the very small gland that runs through each vein of the normal leaf. In some cases the abnormal glands have acicular trichomes projecting into their cavities.


externallink: https://www.biodiversitylibrary.org/item/99818#page/21/mode/1up
description:
  Chermes abietis Choi.

  Picea abies (L) Karst.
  Picea mariana (Mill) B.S.P.

  A polythalamous gall produced by the swelling of the base of the young shoots. Since the twigs are not usually killed the galls are sur- mounted by a variable length of normal stem. The galls in general vary from conoidal to nearly spherical in shape, but in some cases, owing to the stimulation not having aftected the entire circumference of the stem, the gall does not extend completely around it and is consequently less regular in outline. The surface of the gall is covered with the en- larged bases of the aborted needles. These give a faceted appearance to the gall and produce a likeness to a miniature pineapple. 

  Dimensions: — Longer diameter 2-3 cm.; shorter diameter 1-2 cm. 

  The gall in this case is a joint production of the cortex of the stem and the bases of the leaves of the host. The cells of the epidermis, lining the gall cavities, in some cases have been prolonged to form very short trichome-like structures. The hairs at the aperture of exit, as seen in Fig. II, are composed of one or two cells. The resin ducts that occur in the normal cortex are found consider- ably enlarged in the gall. In addition to these, there are out near the gall periphery numerous smaller resin ducts, as shown near the margin of Fig. II, that do not have corresponding structures in the unstimulated tissues. These additional ducts pass in from the swollen bases of the aborted leaves. A cross section near the base of these leaves cuts from four to six resin ducts, while a normal leaf does not contain more than two of these structures. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/22/mode/1up
description:
  Pachypsylla celtidis-mamma Riley. Host CelHs occidentalis L. A complicated form of pouch-gall produced in the mesophyll of the leaf of the host. On the upper surface of the leaf the gall is indicated by a decided depression in the centre of which is a slight elevation that marks the opening of the gall. The part projecting from the lower surface, is oblate-spheroidal in shape, attached to the leaf by a slightly tapering cylindrical stalk. The average number of galls found on a leaf is usually about ten, but in some cases much higher. The surface of the gall is smooth except for a few fine scattered hairs, glaucous and greenish- yellow in colour. Dimensions: — Height from point of attachment 6-7 mm.; width 7-8 mm. The anatomical structure of this gall shows it to be a more complex type than any other of the Hemiptera discussed in this paper. Besides the folding of the leaf the blade has been further changed in thickness and in the character of the cells. The production of the greater part of the abnormal tissue is due to a wide, well differentiated cambium layer, that extends right across the gall and at its margin passes into the tissues of the normal leaf between the palisade and the spongy parenchyma (Fig. 15). The larval chamber is lined by this cambium sheath which thus functions as a nutritive layer. Bordering this zone is a well developed protective tissue composed of cells with uniformly thickened walls. The sclerenchyma is laminated and pene- trated by branched canals, presenting the same character as that found in the galls of the Cynipidae. Outside of this protective zone lies the chief mass of the gall, com- posed of thin-walled irregularly shaped cells, as illustrated in Fig. 15. Typical cells of the protective sheath are also found scattered throughout this tissue. As the gall becomes older these cells increase in number.


externallink: https://www.biodiversitylibrary.org/item/99818#page/38/mode/1up
description:
  Rhabdophaga batatas Walsh.

  "On Salix humilis Marsh. A polythalamous gall of very variable shape and size, pale green when young, the colour of the bark when mature, growing on twigs .06-. 19 inch in diameter and always some distance from the tip of the twig. Sometimes it resembles a small kidney-potato pierced lengthways by a twig, and has then most generally a smooth polished surface studded with a few buds, one or two of which occasion- ally give birth to a shoot, and it then reaches 1.35 inch in length and .6 inch in diameter. Sometimes it resembles a young apple pierced lengthways by a twig and attains a diameter of .3 inch." — Walsh.** In this gall the larval cells are situated in the pith of the host plant, just inside the line of the fibro-vascular bundles. The epidermis has a much thicker cuticle than that borne by a normal stem of corresponding age. The cortex is approximately four times as thick as the cortex of the normal stem. This is due principally to the increased size of the cells. The cells of the nutritive layer are very similar to those of the surrounding tissues but a well marked protective zone defines its outer limits. This is clearly shown in Fig. 25. The cells of the protective zone present a characteristic very rare in Dipterous galls, although frequently found in the Cynipid galls, namely, the walls of the cells are not uniformly thickened but are much heavier on the side next the nutritive zone. This unequal sclerification is illustrated in Fig. 26. Crystals of calcium oxalate, that were so characteristic a feature of this zone in C. triticoides Walsh, seem to be entirely absent in this gall.


externallink: https://www.biodiversitylibrary.org/item/99818#page/36/mode/1up
description:
  Cecidomyia triticoides Walsh.

   "On Salix cordata Muhl. A polythalamous woody gall .70-1.23 inch long and .30-. 37 inch in diameter, bearing a remote resemblance to a head of wheat with the kernels elongated, naked, pointed and very protuberant, its general outline oval or elongate-oval, and formed by the swelling of a twig to 2 or 3 times its former diameter, the swelled portion being very much contracted longitudinally, so as to bring each kernel- like bud nearly or quite into contact with the base of the one that pre- cedes it in the same row, the whole number being arranged in four irregular rows."— Walsh.

  The larval chambers in this gall are placed usually along the line of the fibro-vascular bundles of the stem, and wherever a chamber is situated the vascular tissues are not developed. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/39/mode/1up
description:
  Rhabdophaga strobiloides Walsh.

  Host Salix cordata Muhl. [eriocephala]

  "The galls are very uniform in size and form, usually top-shaped, some inclining to spherical, a little oblate below and prolate above, and as the female oviposits but one egg in the terminal bud of the willow shoot, the galls are terminal and monothalamous. "The gall is a rather tightly and regularly arranged mass of from 70 to 80 aborted leaves, representing perhaps about i m. of the leafage of a normal branch. "The average measurement of 200 galls was 12 mm. X15 mm., and the length of the deformed part of the branch included in the gall around which the aborted leaves were packed was 6 mm." — Brodie. 

  The leaves that constitute the principal mass of this gall do not take any part in supplying the larva with food. The tissue that has this function is composed of a mass of small, thin-walled cells. It terminates the stem axis and the larva is in immediate contact with it (Fig. 24). This tissue which really furnishes a nutritive layer seems to originate from a cambium-like tissue at the base of the mass of cells. An important factor in the production of this gall is the practical cessation of growth of the bud axis. The aborted leaves that compose the gall exhibit very slight anatomical aberrations. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/44/mode/1up
description:
  Pontania pisum Walsh

  on S. discolor Muhl.

  "On Salix discolor. A subspherical, pea-like, hollow, pale yellowish- green gall, always growing on the under side of the leaf and almost always from one of the side veins (in one case from the midrib), and attached to the leaf by only a minute portion of its surface; 0.18 to 0.28 inch in diameter and a few miniature, only 0.08 inch in diameter. Almost invariably there is but one gall to the leaf, but on four leaves there were two, and occasionally two are confluent. Surface in some smooth and even without pubescence; in others a little shriveled, generally studded in the medium-sized ones with four to twelve small, robustly conical nipples, which in the larger ones have burst into a scabrous brown scar. Only in three out of sixty-two was there any rosy cheek as in P. pomum. The point of attachment is marked on the upper side of the leaf by a brown sub-hemispherical depression." — Walsh .

  Walsh is incorrect in supposing that this gall originates from a midrib or vein. A section shows that it is clearly a product of the mesophyll and is attached to that part of the leaf. The side vein, near which it is always placed, is cut by the ovipositor, however, and vascular strands pass out from it into the gall body. 

  The mature gall consists of a peripheral layer of thin-walled cells, irregular in outline surrounding a central cavity (Fig. 81). This tissue is clearly derived from the mesophyll and epidermis of the leaf, but a stage was not secured young enough to show the relative amounts produced from each. The epidermis bears numerous lenticels, organs which Kuster mentions as occurring on the gall produced by Pontania salicis. 

  At the point of attachment of the gall the blade of the leaf is strengthened by several rows of cells derived from the upper epidermis and the palisade parenchyma, as shown in Fig. 81. These cells seem to have remained unmodified in any way, since their arrangement in rows is still clear in fairly old stages of the gall. Consequently they differ very markedly from the irregularly arranged cells of the main part of the gall body.


externallink: https://www.biodiversitylibrary.org/item/99818#page/42/mode/1up
description:
  Euura S. gemma Walsh.

  "On Salix humilis. The lateral bud of a twig enlarged so as to be twice or thrice as long, wide and thick as the natural bud before it begins to expand in the spring ; its external surface otherwise entirely unchanged both in texture and colour. Internally, instead of the normal downy embryo leaves, it contains early in the autumn a homogeneous grass-green fleshy matter, which is afterwards gradually consumed by the larva, leaving nothing at last but a mere shell partly filled with excrement. The gall is monothalamous, sometimes one only on a twig, some- times two or three or more at irregular intervals, very rarely as many as three or four formed out of three or four consecutive buds. 

  Length .17 to .36 inch 
  Breadth .10 to .17 inch. "— Walsh.

  The anatomy of this gall presents little differentiation of tissue. A cross section shows that the entire mass of the gall consists of small thin-walled cells, shown in Fig. 68. The bud scales surrounding this group of cells resemble those of the normal bud except that the cuticle of the epidermis is abnormally thickened. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/43/mode/1up
description:
  Euura S. ovum Walsh.

  "On Salix cordata [eriocephala]. An oval or roundish, sessile, monothalamous swelling, .30 to .50 inch long, placed lengthways on the side of small twigs, green wherever it is smooth, but mostly covered with shallow longitudinal cracks and irregular rough scales which are pale opaque brown. Its internal substance fleshy in the summer like that of an apple, but with transverse internal fibres. When ripe in the autumn filled with reddish-brown spongy matter, with close-set transverse internal fissures at right angles to the axis of the twig. On cutting down to the twig at any time a longitudinal slit about .20 inch long becomes plainly visible." — Walsh . 

  As already noted the host of this gall in this locality is Salix humilis, it remains to be determined whether there are two distinct species of producers or one species with two hosts [Zinovjev and Smith imply this is more likely [Euura salicisovulum](https://www.gallformers.org/gall/3652)]. Walsh's description of the gall on Salix cordata corresponds to the form occurring here on S. humilis.

  The ovipositor of the producer has in this case made a longitudinal cut in the stem. A transverse section at the place where the gall is located shows that this wound extends in from the epidermis to the boundary of the pith. The activity of the young tissues, abnormally stimulated, soon fill this fissure with a mass of small, angular parenchyma. The rapid division of these cells forces the exposed edges of the cortex and central cylinder apart so as to form a wedge-shaped opening which is filled up with the gall mass (Fig. 71). It should be stated that the newly formed cells originate mainly from the division of a cambium bordering the pith at the bottom of the fissure. But other tissues also respond to the stimulation initiated by the ovipositor of the insect. Thus a section of the stem at a short distance from the gall shows that the outlying cambium has become abnormally active and has produced a layer of bast nearly one-third thicker than that found in the normal stem. Likewise the activity of a cork-cambium layer has thrown off a strongly cuticularized epidermis present in the earlier developmental stages .


externallink: https://www.biodiversitylibrary.org/item/99818#page/43/mode/1up
description:
  Euura S. ovum Walsh.

  "On Salix cordata [eriocephala]. An oval or roundish, sessile, monothalamous swelling, .30 to .50 inch long, placed lengthways on the side of small twigs, green wherever it is smooth, but mostly covered with shallow longitudinal cracks and irregular rough scales which are pale opaque brown. Its internal substance fleshy in the summer like that of an apple, but with transverse internal fibres. When ripe in the autumn filled with reddish-brown spongy matter, with close-set transverse internal fissures at right angles to the axis of the twig. On cutting down to the twig at any time a longitudinal slit about .20 inch long becomes plainly visible." — Walsh . 

  As already noted the host of this gall in this locality is Salix humilis, it remains to be determined whether there are two distinct species of producers or one species with two hosts [Zinovjev and Smith imply this is more likely [Euura salicisovulum](https://www.gallformers.org/gall/3652)]. Walsh's description of the gall on Salix cordata corresponds to the form occurring here on S. humilis.

  The ovipositor of the producer has in this case made a longitudinal cut in the stem. A transverse section at the place where the gall is located shows that this wound extends in from the epidermis to the boundary of the pith. The activity of the young tissues, abnormally stimulated, soon fill this fissure with a mass of small, angular parenchyma. The rapid division of these cells forces the exposed edges of the cortex and central cylinder apart so as to form a wedge-shaped opening which is filled up with the gall mass (Fig. 71). It should be stated that the newly formed cells originate mainly from the division of a cambium bordering the pith at the bottom of the fissure. But other tissues also respond to the stimulation initiated by the ovipositor of the insect. Thus a section of the stem at a short distance from the gall shows that the outlying cambium has become abnormally active and has produced a layer of bast nearly one-third thicker than that found in the normal stem. Likewise the activity of a cork-cambium layer has thrown off a strongly cuticularized epidermis present in the earlier developmental stages.


externallink: https://www.biodiversitylibrary.org/item/99818#page/43/mode/1up
description:
  Undescribed Sawfly Gall (Euura N.S.) on Salix serissima Fernald.

  This gall is produced by the abnormal swelling of the petiole of the leaf. The leaves infected are those borne on the branchlets from which spring the pistillate catkins. In the majority of cases, the leaf that bears the gall is the one from the axil of which the peduncle of the catkin arises. The swelling is so close to the branchlet that after the leaves have fallen, the gall appears to have originated from it. This misleading appearance is due to the petiole of the leaf breaking just above the gall. The galls are cone-shaped with the apex towards the blade of the leaf. They are marked deeply by three or four grooves that meet at the tip. 

  Dimensions: — Height of gall 7-8 mm.; diameter at base 6-7 mm. 

  The anatomy of this gall presents a very compact tissue, owing to the cells being placed close together without intervening air spaces. The very much thickened cuticle of the epidermis is the greatest departure from the normal tissue. Of the three bundles of the normal petiole two are lacerated by the ovipositor of the insect, as shown in Figs. 69, 70. In the mature gall the halves of these two are found in four widely separated regions (Fig. 69), owing to the abundant production of tissue between them. Indeed practically all the abnormal tissue is produced from the undifferentiated cells stimulated by the cutting of the bundles.


externallink: https://www.biodiversitylibrary.org/item/99818#page/45/mode/1up
description:
  Pontania pomum Walsh.

  "On Salix cordata (and very rarely on S. discolor). A smooth, fleshy, sessile, globular or slightly oval, monothalamous gall, resembling a miniature apple, .30 to .55 inch in diameter, growing on one side of the midrib of a leaf, and extending to its edge or sometimes a little beyond it. The principal part of the gall generally projects from the under side of the leaf, and only about one-sixth of its volume from the upper side, although very rarely it is at most equally bisected by the plane of the leaf. Scarcely ever more than one gall on a leaf and very rarely two of them, more or less confluent so as to seem like one kidney-shaped gall. Ex- ternal colour greenish-yellow, generally with a rosy cheek like an apple especially on the upper surface and often with many dark little dots on its surface." — Walsh .

  The ovipositor of the producer of this gall has been thrust laterally through the midrib of the leaf into the mesophyll. The wound has completely severed the bundle of the midrib, as seen in Fig. 76. 

  The full-grown gall presents an epidermis with a very thick cuticle. The remainder of the gall consists of a complex of thin-walled cells arranged so as to constitute a typical aeriferous tissue (Fig. 77). A similar arrangement of cells is not found in the normal leaf, the mesophyll of which consists of a fairly compact tissue. The vascular strands growing out from the wounded bundle form a complete ring around the gall, situated about half way between the epidermis and the centre. 

  I was successful in obtaining this gall at such an early stage that the egg membrane was still unbroken (Fig. 76). This phase shows that the epidermis, the palisade and the spongy parenchyma mutually take part in the gall production. Counting along a line passing through the centre, four of the cell layers are seen to have arisen from the lower epidermis and six from the upper, eight from the palisade and fifteen from the spongy parenchyma of the leaf. Hence it is noteworthy that the new tissues are not the product of a cambium but have been contributed to by every morphological region of the leaf. The cells that are produced at this stage are in rows generally in exact alignment with the cells from which they have arisen. They thus do not have the arrange- ment of the aeriferous tissue of later stages to which they give rise. The cuticle, so marked a feature of the older stages of the epidermis, is exceedingly thin. The epidermis bears trichomes springing from the bottoms of deep pits (Fig. 76). This condition has arisen through the circumstance that the primary epidermal cells from which hairs have grown out have not experienced the periclinal divisions participated in by their fellows and so have been left far below the general surface as shown in the text fig. below.


externallink: https://www.biodiversitylibrary.org/item/99818#page/46/mode/1up
description:
  Pontania desmodioides Walsh.

  "On Salix humilis. A smooth, flattish, fleshy, sessile, yellowish- green monothalamous gall of a semicircular outline, the chord of the semicircle adjoining the midrib of a leaf; its general shape like the seed of a Desmodium or like the so-called "quarter" of an orange, the thin inside edge of the "quarter" closely hugging the midrib of the leaf, and the robust outer surface not biangulated but rounded off. No rosy cheek. The volume of the gall is generally about equally divided between the upper and lower sides of the leaf but sometimes the lower portion is rather the larger. Usually there is but a single gall on a single leaf, but occasionally there are two of them, either on the same side or on opposite sides of the midrib." — Length .23 to .50 inch Walsh.

  When mature this gall shows in cross section a cavity surrounded by a peripheral layer of little differentiated tissue. The epidermis has given rise to a very thick cuticle that is not present in the normal leaf. The bundle of the midrib has been injured only slightly by the ovipositor of the producer. The vascular strands given off from it almost encircle the gall along a line half way in from the epidermis. 

  A stage of the gall so young that the larva was unhatched shows the gall tissue to have been produced by cell division in the upper epidermis, the spongy parenchyma and the palisade parenchyma of the normal leaf (Fig. 80). At the thickest part of the gall, when it is in this stage, the upper epidermis has produced four layers of cells, the spongy and palisade parenchyma seven layers each. The lower epidermis has not divided as yet, and probably takes no part in the production of the gall. The abnormal cells from the palisade parenchyma show clearly their origin by their arrangement in rows at right angles to the surface of the leaf. The cells produced by the spongy parenchyma, on the other hand, are not regularly placed but include air spaces. The result is that the abnormal tissue in this case also resembles the normal tissue from which it is derived. 

  This stage of the gall shows that the cavity present in the mature gall has arisen between the tissue produced by the spongy and that derived from the palisade parenchyma of the normal leaf. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/47/mode/1up
description:
  Pontania hyalina Norton.

  "Fleshy galls occurring in two parallel rows, one on either side of the midrib, sometimes touching but not originating from the latter, and rarely extending to the edge of the leaf; sometimes as many as twenty on a single leaf; in other cases confined to a row on one side of the leaf or occasionally occurring singly; shape irregular elongate-ovate, projecting equally on both surfaces of the leaf; length 7 to 10 mm.; the abortive ones smaller. Colour on upper side more or less brownish red ; beneath white, with slight purplish tinge." — Marlatt.

  The anatomy of this gall presents scarcely any differentiation of tissue. When mature it consists of a mass of thin-walled chlorophyll- bearing cells, the innermost of which are arranged in rows almost at right angles to the blade of the leaf, as seen in Fig. 75. Cells are so much alike that they afford no clue as to their origin. 

  Again I was able to obtain material so young that the larva was still confined within the egg membrane (Figs. 73, 74). It shows that the spongy parenchyma, the palisade parenchyma and the epidermis of the normal leaf were jointly concerned in the production of the abnormal tissue. The spongy parenchyma has contributed nearly half of the entire mass, the epidermes three layers each, and the row of cells immediately overlying the lower epidermis three layers. The remainder has been derived from the palisade parenchyma. 


externallink: https://www.biodiversitylibrary.org/item/99818#page/48/mode/1up
description:
  Undescribed Sawfly Gall on S. lucida Muhl.

  This gall consists of an enlargement of either the petiole or midrib of S. lucida. Neither of these organs bears, as a rule, more than one gall at a time, but occasionally the petiole of a leaf carries two or even three and the midrib in rare instances two. 

  The midrib galls are fairly regularly elliptical in outline with the shorter diameter across the leaf. The swellings in most cases are nearly equally divided between the upper and the lower leaf surfaces. The petiole galls vary from spherical to ovoid in shape. In the latter case the smaller end of the gall is towards the apex of the leaf. 

  Dimensions of the gall: — Longer diameter 6-12 mm.; shorter diameter 3-7 mm. 

  The very marked proliferation of tissue in this gall is not accompanied by a differentiation that presents many points of interest. The cells are larger than those of the normal leaf and the nuclei are correspondingly larger. The bundle is cut nearly through by the ovipositor (Fig. 82). The free ends of the bundle thus stimulated grow out until in some cases they almost surround the gall. This elongation is produced in part by the increased diameter of the vessels but also by the production of new cellular elements. 

  The pith, exposed by the cutting of the bundle, produces almost all the abnormal tissue (Figs. 83, 84), but the cortex contributes some. The cells are arranged in curved lines that pass across from one elon- gated end of the bundle to the other. Between these rows are many air spaces which are elongated in the direction of the lines of cells (Fig. 84). 


externallink: https://www.biodiversitylibrary.org/item/99818#page/49/mode/1up
description:
  Undescribed Sawfly Gall on Salix humilis

  This is a monothalamous gall produced by the abnormal swelling of the leaf petiole of S. humilis. It is conoidal in shape with a long tapering apex which is towards the blade of the leaf. As it is situated at the base of the petiole the uniform enlargement of that organ is often pre- vented by the axillary bud. This causes the gall to project to a greater extent on the outside of the petiole and produces an irregularity in the outline of the gall. The surface is quite glabrous in spite of the fact that the epidermis of the leaf is decidedly pubescent. 

  Dimensions : — Length of gall 6-9 mm. ; width 3-4 mm. 

  Nearly the entire mass of this gall originates from the vascular bundle of the petiole which has been stimulated to activity by the in- sect's ovipositor. The small thin-walled cells of the gall substance spring from a cambium layer produced in the pith of the bundle near the ovipositor wound. The cells arising from this tissue force the severed ends of the bundle apart until the vascular elements form only a narrow line of cells between the gall proper and the cortex of the petiole; it is shown at this stage in Fig. 85. This cortex is not materially thickened but shows signs of stimulation in that there appears a small amount of aeriferous tissue located near the place of entrance of the ovipositor. This tissue is shown on each side of the wound in Fig. 85. This tissue was not found in the normal cortex of the petiole. The cuticle is very much thickened. 


externallink: https://www.biodiversitylibrary.org/page/8972483#page/307/mode/1up
description:
  Euura cosensii n. sp.

  The sawfly gall on the base of the petiole of Salix humilis Marsh, is common in High Park of this city. and last fall it was particularly plentiful. Induced by this fact to forget several unsuccessful attempts to rear the producer, I collected a large number of the galls and kept them during the winter under as nearly natural conditions as possible. A number pupated a couple of inches below the surface of the soil in the breeding jar, and several adults emerged between June 3rd and 10th, S. A. Rohwer, Washington, D.C., to whom specimens were sent, has not yet published his description, but has sent me a manuscript copy of it. The species which has been named Euura cosensi n. sp., is said to be closely connected with Euura nodus Walsh, a form that produces stem galls on Salix longifolia Muhl. From this species it may readily be differentiated by the shape of the sheath and the different sculpture of the head.


externallink: https://www.biodiversitylibrary.org/page/8972483#page/308/mode/1up
description:
  Euura gemma 

  Host: Salix humilis

  In this species, the gall is formed by the abnormal swelling of a lateral bud.

  Range: Toronto Ontario


externallink: https://www.biodiversitylibrary.org/page/8972483#page/308/mode/1up
description:
  Euura ovum

  Host: Salix humilis

  An elongated oval swelling on one side of a twig constitutes the gall in this case. 

  Range: Toronto, Ontario


externallink: https://www.biodiversitylibrary.org/page/8972483#page/309/mode/1up
description:
  Pontania crassicornis Rohwer

  Host Salix humilis

  The gall resembles the well known Pontania pomum, Walsh, in shape, but is considerably smaller. It is densely pubescent and several are usually crowded together on one leaf. 

  Range: Toronto, Ontario


externallink: https://www.biodiversitylibrary.org/page/8972483#page/309/mode/1up
description:
  Pontania desmodioides

  Host Salix humilis

  A smooth, flattish gall with a semicircular outline originating from the mesophyll of the leaf of the host. The last two galls mentioned are abundant in this locality. Especially in the western part of the city the numerous ridges and plains consist largely of sand sorted over and deposited by the wave action of the glacial. Lake Iroquois. In the light soil thus produced pines and oaks flourish and in the open spaces among these Salix humilis finds an ideal habitat. The resulting frequent occurrence of this food plant contributes to the abundance of several of our sawfly galls parasitic on this host.

  Range: Toronto, Ontario


externallink: https://www.biodiversitylibrary.org/page/8972483#page/309/mode/1up
description:
  Pontania hyalina

  Host: Salix alba

  The galls are arranged in two almost parallel rows, one on each side of the midrib of the leaf. This is the most plentiful willow gall in this vicinity. The host has been planted in large numbers and few of these escape infection.

  Range: Toronto, Ontario


externallink: https://www.biodiversitylibrary.org/page/8972483#page/309/mode/1up
description:
  Pontania lucidae

  Host: Salix lucida

  The gall is produced as an enlargement of the petiole or midrib of the leaf. Throughout the district in general this species is not common. 

  Range: Toronto, Ontario


externallink: https://www.biodiversitylibrary.org/page/8972483#page/309/mode/1up
description:
  Pontania pisum

  Host: Salix discolor

  An almost spherical pea-like gall, with a small point of attachment to the leaf of the host. Only rarely found in the locality. 

  Range: Toronto, Ontario


externallink: https://www.biodiversitylibrary.org/page/8972483#page/309/mode/1up
description:
  Pontania pomum

  Host: Salix cordata [eriocephala]

   Among the numerous sand ridges, referred to previously, are many streams and ponds of water. These are skirted, often for long stretches, by a screen of the heart-leaved willow. The majority of these host plants are always infested with this gall.

  Range: Toronto, Ontario


description:
  [Euura pyriformis](https://www.gallformers.org/gall/3556) on Salix eastwoodiae conforms to Smith's description of Type IV leaf galls. 


description:
  Euura pyriformis conforms to Smith's description of [Type IV leaf galls.](https://www.gallformers.org/gall/3660)


externallink: https://www.biodiversitylibrary.org/item/33539#page/262/mode/1up
description:
  Pontania petiolaridis New Species

  An almost spherical, sawfly gall is produced on the leaves of Salix petiolaris Sm., a native willow that is not uncommon in low ground near the city. The deformity closely resembles the conspicuous apple-like gall of Pontania pomum Walsh, but differs from this species in some details of structure. The host plants of the two galls differ as Pontania pomum is restricted almost, if not entirely, to Salix cordata [eriocephala] Muhl. In their attachment to the leaves of their hosts they also vary as the species on Salix petiolaris is almost equally divided by the blade, while Pontania pomum projects, only very slightly, from the upper side of the leaf. Further, the former species is hollow from the earliest stages, but the latter only becomes so when eaten out by the larvae. A number of the galls from Salix petiolaris Sm. were collected in 1915, just before the fall of the leaves, and were kept, out-of-doors, in jars containing earth, during the winter. The adults began to emerge April 15th, and were sent to Mr. S. A. Rohwer, Washington, D.C., who has kindly replied as follows: "I have made a preliminary examination of the species and find that it may easily be distinguished from Pontania pomum and that it comes near to P. pisum. I think the species is undoubtedly new." 

  An interesting observation was made concerning this new species of sawfiy, namely that the aperture of exit is prepared a considerable length of time before the larvfe leave the galls. Just what conditions finally prompt their departure and why their means of escape have to be ready, are points not yet cleared up. Since all sawfly galls are well advanced in development before the larvae are hatched, it is safe to conclude that the chief stimulus to abnormal growth must emanate from the ovipositor of the insect. The sawflies, when depositing eggs, clasp the opening buds with 'their legs and insert their sawlike ovipositors into the young leaves from the under side. Into each of the incisions, thus made, an egg is injected. The larvae, as soon as hatched, commence to feed upon the substance in the interior of the gall, but leave the rind uninjured. Since the pear-slug, Eriocampa cerasi Peck makes a similar incision in the leaf, without causing an abnormal production of tissue, it is highly probable that in the case of the sawfly gall-producers, the stimulus is not due to the mechanical effect of the cutting, but to a chemical action arising from the introduction of some substance by the ovipositor of the insect. 

  Range: Toronto, Ontario


externallink: https://www.biodiversitylibrary.org/item/53483#page/333/mode/1up
description:
  Pontania amentivora, new species

  This species lives, in the larval stage, in the pistillate catkins of a small species of Salix and causes the destruction of the ovaries and the premature forming of "cotton."

  Range: VA


externallink: https://www.biodiversitylibrary.org/item/53483#page/337/mode/1up
description:
  Euura cosensii, new species

  Toronto, Ontario. Described from three females (one, type) and four males (one, allotype) which were reared from galls from the petiole of Salix humilis, material collected and reared by A. Cosens, for whom the species is named. This gall is well described by Cosens, and the description need not be repeated here.


externallink: https://www.biodiversitylibrary.org/item/32782#page/324/mode/1up
description:
  Euura serissimae, new species

  Toronto, Ontario, Canada. One female bred from galls made on the leaf petiole of Salix serissima, by A. C. Cosens.


externallink: https://www.biodiversitylibrary.org/item/32782#page/325/mode/1up
description:
  Pontania crassicornis, new species

  Toronto, Ontario, Canada. One male bred from galls on Salix humilis, by A. Cosens.


externallink: https://www.biodiversitylibrary.org/item/32782#page/326/mode/1up
description:
  Pontania lucidae, new species

  Toronto, Ontario. Males and females bred from galls on Salix lucida, by A Cosens.


externallink: https://www.biodiversitylibrary.org/item/99818#page/47/mode/1up
description:
  Undescribed Sawfly Gall {Pontania N.S.) on Salix humilis Marsh. 

  This is a monothalamous gall found on the leaves of Salix humilis. It is spherical in shape and in that feature resembles P. pomum, but in other respects it differs very markedly. It extends from the side of the midrib almost out to the margin of the leaf and is divided into two hemispheres by the leaf blade. In consequence the gall protrudes nearly equally from each leaf surface. Usually there are two or three galls on a leaf. When two are present they come in contact with the mid- rib at the same place but on opposite sides, as illustrated in Fig. 79. In a few cases four and even five galls were found on one leaf. The galls are pubescent but not as densely as the under surface of the leaf. 

  Dimensions: — Average diameter 1 cm. 

  The mesophyll of the leaf and the upper epidermis are mutually concerned in the production of this gall. In one, sufficiently immature to show the relative amount of tissue arising from each source, it was found that the upper epidermis had produced two cell layers, while the lower had not responded to stimulation ; and that the palisade and spongy parenchyma had each produced one-half of the remaining mass. The hollow in the gall, present from the earliest stages, has been formed between the tissue arising from the palisade and the spongy parenchyma respectively. 

  When only one gall originates from the midrib at any point, the vascular bundle is cut approximately half through (Fig. 78). But more frequently two galls are located opposite one another, one on each side of the midrib, in which case the two incisions meet and completely sever the bundle, as seen in Fig. 79. 

  Vascular strands pass almost completely around the gall, along a line half way between the epidermis and the gall cavity. These strands originate from the midrib in the neighborhood of the injury and pass in opposite directions. 


description:
  A moderately sized, sparsely to densely long-hairy globular gall narrowly attached near the midrib on the lower side of leaves of Salix bebbiana, single or in rows along the length of the leaf. The surface is yellow to pink-red and sparsely dotted with darkened lenticels. They differ from [this woolly gall](https://www.gallformers.org/gall/3635) also tentatively known from Salix bebbiana in their much smaller profile from the upper side of the leaf, their thinner layer of hairs not completely obscuring the surface, and their orientation along the length of the leaf rather than across the midrib. Observed in Minnesota in June and in Ontario in August. 


description:
  Large, hairless, yellow-green, irregularly globular galls largely on the lower side of leaves of Salix bebbiana. These galls resemble [Euura salicispomum](https://www.gallformers.org/gall/3550) on Salix eriocephala, and like that species, a wide portion of the gall is visible from the upper side of the leaf but it does not project substantially higher than the leaf. The surface below is smooth but speckled with white or red-brown lenticels, which are absent from the upper side. Observed in Minnesota in June.


description:
  Moderately sized, hairy or hairless, green-yellow to deep red, globular galls, often spotted with white or red-brown lenticels, on leaves of Salix hookeriana. These galls typically extend less than the full distance between the midrib and leaf edge, project much more on the lower side than above, and are found either alone or in groups of up to 5. Observed in northern California and Oregon from June to October.


externallink: https://www.biodiversitylibrary.org/page/29650370#page/118/mode/1up
description:
  Euura macgillivrayi

  Gall: on Salix luteosericea Rydb. [exigua]; a gradual enlargement of the twig about 30 mm. long. 

  Range: Boulder, Colorado, at the mouth of Boulder Canyon. Adults appearing early in May in the field, earlier in the laboratory (S. A. Rohwer). (Type locality.)


externallink: https://www.biodiversitylibrary.org/page/29650370#page/118/mode/1up
description:
  Euura bebbianae

  Gall: an abrupt laternal swelling on twigs of Salix bebbiana. 

  Range: Boulder, Colorado. Many males and females bred on galls on Salix bebbiana collected near the mouth of Boulder Canyon (S. A. Rohwer). (Type locality.) 


description:
  Large, white-hairy globular galls on the lower side of the leaf of Salix alaxensis, presenting a small portion above the leaf. This gall differs from the similar [woolly gall](https://www.gallformers.org/gall/3635) known from Salix bebbiana in its host and its orientation relative to the midrib. Rather than occurring in a pair on either side of the midrib, this gall occurs in a pair along the length of the midrib. Observed in Alaska in July. 


description:
  Rabdophaga strobiloides

  Host: originally found on Salix cordata [Muhl. =eriocephala] in Illinois, the gall is known from many other willow species. 

  Salix
  Bud gall comprising many modified leaves
  Leaves generally appressed, imbricate, simulating a pine cone
  Leaves wider than long, apex of gall attenuate, closed, the twig beneath the gall straight

  These galls are one of the most common on willow. Occasionally some are found with the apical leaf edges slightly recurved. 

  [Two drawings appear on page 277, Figure 405-6]

  Range: New England to CA

  [Note referring to this and several other bud gallers]: Leaves of these galls are typically largest on the outside of the gall but narrow considerably toward the center of the gall. In this key only the outer leaf shape of the mature gall is described. The gall formers are always at the heart of the gall, surrounded by linear leaves. The larva feeds upside down and reverses position before pupation. The gall makers have one generation per year, are full grown in fall, overwinter in the gall in a cocoon, and pupate the following spring. Infested twigs are considerably stunted.

  Inquiline, found among leaf scales: Dasineura albovittata


description:
  Rabdophaga salicisstrobiliscus

  Host: Salix discolor, rostrata [bebbiana]

  Salix
  Bud gall comprising many modified leaves
  Leaves generally appressed, imbricate, simulating a pine cone
  Leaves triangular, narrowing toward tip to produce an open “beak,” or twig recurved below gall
  Tip of gall beaklike; twig beneath gall not recurved

  The original reporter of this gall (Walsh 1864) suggested that it might only be an aberrant form of that formed by [R strobiloides](https://www.gallformers.org/gall/1634)

  [No drawing is given for this gall]

  Range: IL

  [Note referring to this and several other bud gallers]: Leaves of these galls are typically largest on the outside of the gall but narrow considerably toward the center of the gall. In this key only the outer leaf shape of the mature gall is described. The gall formers are always at the heart of the gall, surrounded by linear leaves. The larva feeds upside down and reverses position before pupation. The gall makers have one generation per year, are full grown in fall, overwinter in the gall in a cocoon, and pupate the following spring. Infested twigs are considerably stunted.


description:
  Rabdophaga salicisgnaphalioides

  Host: Salix candida, humilis

  Salix
  Bud gall comprising many modified leaves
  Leaves generally appressed, imbricate, simulating a pine cone
  Leaves triangular, narrowing toward tip to produce an open “beak,” or twig recurved below gall
  Tip of gall not beaklike; twig beneath gall recurved

  Galls are small than those of [strobiloides](https://www.gallformers.org/gall/1634), only about 5-10 mm long and 5 mm wide.

  [A drawing of this gall appears on page 277, Figure 407]

  Range: IL

  [Note referring to this and several other bud gallers]: Leaves of these galls are typically largest on the outside of the gall but narrow considerably toward the center of the gall. In this key only the outer leaf shape of the mature gall is described. The gall formers are always at the heart of the gall, surrounded by linear leaves. The larva feeds upside down and reverses position before pupation. The gall makers have one generation per year, are full grown in fall, overwinter in the gall in a cocoon, and pupate the following spring. Infested twigs are considerably stunted.


description:
  Rabdophaga salicisbrassicoides

  Host: Salix longifolia [interior]

  Salix
  Bud gall comprising many modified leaves
  Leaves loose, exfoliate, forming an open rosette
  Leaves conspicuously longer than wide

  [A drawing of this gall appears on page 277, Figure 408]

  Galls range from 5-25 mm in diameter, the size evidently dependent on the size of the affected twig. A predaceous cecidomyiid Lestodiplosis septemmaculata has been reared from these galls.

  Range: IL

  [Note referring to this and several other bud gallers]: Leaves of these galls are typically largest on the outside of the gall but narrow considerably toward the center of the gall. In this key only the outer leaf shape of the mature gall is described. The gall formers are always at the heart of the gall, surrounded by linear leaves. The larva feeds upside down and reverses position before pupation. The gall makers have one generation per year, are full grown in fall, overwinter in the gall in a cocoon, and pupate the following spring. Infested twigs are considerably stunted.


description:
  Rabdophaga saliciscoryloides

  Host: Salix ?discolor

  Salix
  Bud gall comprising many modified leaves
  Leaves loose, exfoliate, forming an open rosette
  Leaves almost as wide as long
  Galls leaves open, flared, the gall shorter than wide

  [A drawing of this gall appears on page 277, Figure 412]

  Galls are 5-7 cm long and 5-10 cm in diameter. The difference between these and galls of [R. salicisbrassicoides](https://www.gallformers.org/gall/1626) and [R. salicisrhodoides](https://www.gallformers.org/gall/3531) may be only superficial.

  Range: IL

  [Note referring to this and several other bud gallers]: Leaves of these galls are typically largest on the outside of the gall but narrow considerably toward the center of the gall. In this key only the outer leaf shape of the mature gall is described. The gall formers are always at the heart of the gall, surrounded by linear leaves. The larva feeds upside down and reverses position before pupation. The gall makers have one generation per year, are full grown in fall, overwinter in the gall in a cocoon, and pupate the following spring. Infested twigs are considerably stunted.


description:
  Rabdophaga salicisrhodoides

  Host: Salix humilis

  Salix
  Bud gall comprising many modified leaves
  Leaves loose, exfoliate, forming an open rosette
  Leaves almost as wide as long
  Gall leaves more sessile, the gall longer than wide

  [A drawing of this gall appears on page 277, Figure 410]

  The gall simulates an elongated rose blossom. It is 1-2 cm in diameter and 2-5 cm long.

  Range: IL

  [Note referring to this and several other bud gallers]: Leaves of these galls are typically largest on the outside of the gall but narrow considerably toward the center of the gall. In this key only the outer leaf shape of the mature gall is described. The gall formers are always at the heart of the gall, surrounded by linear leaves. The larva feeds upside down and reverses position before pupation. The gall makers have one generation per year, are full grown in fall, overwinter in the gall in a cocoon, and pupate the following spring. Infested twigs are considerably stunted.


description:
  Rabdophaga saliciscornu

  Host: Salix humilis

  Salix
  Bud gall not comprising imbricated, modified leaves
  Complex gall; lateral bud deformed into elongate, thin-walled, hornlike structure

  [A drawing of this gall appears on page 277, Figure 411]

  Galls are monothalamous, 10-20 cm long, about 2 mm wide, pointed at the tip, and slightly curved.

  Range: IL


description:
  Rabdophaga rigidae

  Host: many species of willow

  Salix
  Bud gall not comprising imbricated, modified leaves
  Simple gall; terminal bud greatly swollen

  [A drawing of this gall appears on page 277, Figure 413]

  This is probably the most common of the willow galls. Galls are monothalamous, subglobular to tapered, 1-3 cm long, and 0.5-1 cm wide. The galls are first evident in May. A few leaves often begin to grow beyond the gall but soon die. After the adults emerge from the galls the following spring, the buds usually die, but new growth may develop from around the base of the gall. 

  Range: New England to the West Coast; eastern Asia, including Japan


description:
  Rabdophaga salicistriticoides

  Host: Salix cordata [eriocephala] and humilis

  Salix
  Swollen twigs
  Foreshortened twig, the buds close together

  [A drawing of this gall appears on page 277, Figure 409]

  Buds may be so close as to resemble kernels on a wheat head. The enlargement is 2-4 cm long. Larvae overwinter in the galls. In spring the pupae escape from the kernellike buds.

  Range: New York and IL


description:
  Rabdophaga salicisbatatus

  Host: Salix humilis and many other species of Salix

  Salix
  Swollen twigs
  Internodal twig swelling without foreshortening the stem
  Twig swelling very large, soft, sometimes resembling a potato in shape

  [A drawing of this gall appears on page 282, Figure 416]

  This gall is variable but usually polythalamous and bulging abruptly out of the twig. One generation occurs per year. Adults emerge from the galls in spring. An apparently inquilinous cecidomyiid, “Cecidomyia” orbitalis Walsh, was reportedly reared from these galls. The type specimens are lost, so the species cannot be identified to genus.

  Range: New England to California


description:
  Dasineura corticis

  Host: Salix sp.

  Salix
  Swollen twigs
  Internodal twig swelling without foreshortening the stem
  Twig swelling tapered, woody, sometimes barely noticeable

  [No drawing is included for this gall]

  This species was reared in May from small cavities beneath bark. It may be an inquiline or a secondary feeder. The name “Cecidomyia” orbitalis Walsh might be applicable to this Dasineura.

  Range: MA


description:
  Lygocecis packardi

  Host: several species of willow from Massachusetts to Texas

  Salix
  Swollen twigs
  Internodal twig swelling without foreshortening the stem
  Twig swelling tapered, woody, sometimes barely noticeable

  [No drawing is included for this gall]

  L packardi, L porterae, and two other, undescribed species of Lygocecis in the USNM, were reared from enlarged willow stems. These species have sawlike ovipositors evidently used to insert their eggs into willow shoots.

  Range: Massachusetts to Texas


description:
  Lygocecis porterae

  Host: a willow

  Salix
  Swollen twigs
  Internodal twig swelling without foreshortening the stem
  Twig swelling tapered, woody, sometimes barely noticeable

  [No drawing is included for this gall]

  L packardi, L porterae, and two other, undescribed species of Lygocecis in the USNM, were reared from enlarged willow stems. These species have sawlike ovipositors evidently used to insert their eggs into willow shoots.

  Range: New Mexico


description:
  Rabdophaga cornuta

  Host: Salix spp.

  Salix
  Swollen twigs
  Internodal twig swelling without foreshortening the stem
  Twig swelling tapered, woody, sometimes barely noticeable

  [No drawing is included for this gall]

  This is a borer in larger willow stems. Walsh (1864) found it associated with stems affected by R salicisbrassicoides.

  Range: IL


description:
  Rabdophaga ?salicis

  Host: Salix spp.

  Salix
  Swollen twigs
  Internodal twig swelling without foreshortening the stem
  Twig swelling tapered, woody, sometimes barely noticeable

  [No drawing is included for this gall]

  The damage this species does is apparently similar to that of R cornuta. R salicis occurs on many willows in both Europe and Japan; the specimens identified as this species in North America were found on imported nursery stock. They could well be this or some other European species, but American specimens identified in the past as R salicis do not compare exactly with European specimens identified as salicis.


description:
  Rabdophaga salicisnodulus

  Host: Salix spp.

  Salix
  Swollen twigs
  Internodal twig swelling without foreshortening the stem
  Twig swelling tapered, woody, sometimes barely noticeable

  [No drawing is included for this gall]

  This was originally reared from monothalamous galls, but similar galls are often polythalamous, some harboring more than one species. Heavily infested shoots can be killed. The exit holes seen in spring are cut by the pupae. This and other Rabdophaga and Lygocecis spp. Listed probably have only one generation per year. 

  Range: New England to IL


description:
  Dasineura plicata

  Host: Salix sp.

  Salix
  Leaf gall
  Rolled leaf

  [A drawing of this gall appears on page 282, Figure 415]

  Leaves are tightly rolled into a tube. Full-grown larvae form cocoons in the leaves. Adults were reared in May and August. 

  Range: MA and NY


description:
  Iteomyia salicifolia

  Host: Salix sp.

  Salix
  Leaf gall
  Spherical gall protruding from only one side of leaf

  [A drawing of this gall appears on page 282, Figure 414b]

  Galls are monothalamous and about 2 mm in diameter. Full-grown larvae leave the galls in late summer and spin cocoons in which they overwinter.

  Range: NY


description:
  Iteomyia salicisverruca

  Host: Salix humilis and other willows

  Salix
  Leaf gall
  Tube gall, beak on one side of leaf and convex on the other

  [A drawing of this gall appears on page 282, Figure 414a]

  Galls are monothalamous, 2-3 mm in diameter, and often coalesced. The biology is unknown, but larvae presumably leave the galls in the fall, as do larvae of I salicifolia.

  Range: NY, IL, WA, and OR


description:
  [Fritz et al report a higher prevalence of Iteomyia salicifolia on hybrids between Salix eriocephala and sericea than on either parent species]


description:
  [Fritz et al report a higher prevalence of Aculops tetanothrix on Salix eriocephala than on Salix sericea or hybrids of Salix eriocephala and sericea]


description:
  [Fritz et al report finding Rabdophaga rigidae on Salix sericea and hybrids with Salix eriocephala but not on eriocephala alone]


description:
  [Fritz et al report finding Rabdophaga salicisbrassicoides on hybrids between Salix eriocephala and sericea and on both parent species.]


externallink: https://www.biodiversitylibrary.org/page/36665002#page/572/mode/1up
description:
  Oligotrophus salicifolius 

  Galls on Salix humilis, July 12. Same gall on Salix, September 22.

  The irregular, yellowish, red-spotted galls of this species on the leaves of Salix humilis were taken at Karner September 7, 1909, adults being reared in March and April of the following year. The deep orange larvae appear to desert the galls in late fall, spinning oval, yellowish cocoons attached to any hard substance such as a leaf. The gall is very similar to that of [O. capreae](https://bladmineerders.nl/parasites/animalia/arthropoda/insecta/diptera/nematocera/cecidomyiidae/cecidomyiinae/lasiopteridi/oligotrophini/iteomyia/iteomyia-capreae/) Winn. and the adults are evidently closely allied though separable in color characteristics. 

  Gall. Length 2 to 3 mm, irregular, ovoid, monothalamous, yellowish, red-spotted and usually most evident on the under surface of the leaves of Salix humilis. 


externallink: https://www.biodiversitylibrary.org/page/9543087#page/452/mode/1up
description:
  Oligotrophus salicifolius, n. sp.

  Salix
  Leaf galls

  Yellowish, truncate, greenish yellow, lipped gall, diameter 2 mm.


externallink: https://www.biodiversitylibrary.org/item/23810#page/597/mode/1up
description:
  Salicis brassicoides. n. sp. — On Salix longifolia [interior]. 

  Monothalamous, sessile galls, expanding each 0.75 — 2.25 inch, and with the general outline of each spherical or oval, growing in a more or less close-set bunch of 1 — 11, like the sprouts of a cabbage-stump, on twigs which vary in diameter from .10 inch to .50 inch, sometimes from their tips but more generally from their sides, and often with several minute twigs growing from the midst of each bunch of galls, the largest galls generally on the largest twigs. The leaves composing each gall are all sessile, and are on the outside ovate lanceolate or lanceolate, and widely expanded and towards their tips recurved. Towards the tip of the gall they become smaller, slenderer, and gradually less expanded, and in the centre they are quite small, perfectly straight and linear-lanceolate, closely embracing the central cell containing the author of the gall. External leaves with the midrib, and generally some of the branching side-veins, pretty distinct. It is but very rarely that the leaves composing each gall show any traces of the peculiar, widely-removed serratures which characterize the leaves of the willow on which they occur, their edges being almost invariably perfectly entire. The color of the galls when recent, is the same as that of the recent leaves of the willow on which they grow, but at the fall of the leaf they become reddish brown, and after hanging on the twig more than one year, almost black. 

  Described from 19 bunches of galls. Very common near Rock Island, Illinois. The eggs that originate these galls must be laid from the middle of April to the end of May, and by the middle of July the galls have attained their full size. When the twig on which they grow is at all small, it generally dies the next spring.


externallink: https://www.biodiversitylibrary.org/item/23810#page/600/mode/1up
description:
  S. strobiloides O. S. 

  On S. cordata [eriocephala?]. 

  A monothalamous gall like a pine-cone, always on the tips of twigs when young, but often with small shoots of the same year's growth surrounding it, porrect, .50 — .90 inch in its transverse diameter, and in stunted galls where the gall-maker has perished even as small as .20 inch in diameter, generally when viewed laterally with an ovate outline and the tip more or less truncate, occasionally subspherical. The leaves com- posing it are all sessile, closely appressed and imbricate, and all those on the outside are covered with a short, dense, glaucous-white pubescence on their entire exterior surface, and occasionally in a less degree on their interior surface, and are reddish-brown inside when mature, those on the inside of the gall becoming gradually smooth and reddish-brown on their exterior basal portion, and finally throughout. Towards the base of the gall the leaves are orbicular, the basal ones smaller; the next leaves are obovate and with their tips in a semicircle, and as they approach the tip of the gall oblanceolate, and in the inside linear-lanceolate and gradually smaller, slenderer and straighter, till they finally embrace the central cell containing the author of the gall. External leaves, except towards the tip of the gall, with a number of branching veins springing from their base, the midrib scarcely distinct from them by its supe- rior size and throwing out similar branches, all of them obvious on the internal face of the leaf and obsolete on its external face. The tip of the twig from which the leaves spring, both in this and the 4 following species, is constructed as in C s. brassicoides. 

  Described from 30 specimens. Very common and abundant in Rock Island County, Illinois, hundreds of them occurring on, a single bush. None of the leaves composing this gall are ever serrate, as in the willow on which it grows, but always entire. When young and immature, the galls are spherical and are enveloped in a dense mass of foliage, which gradually falls off towards the autumn, and by November the twigs on which they grow, if small, are already killed for an inch or two down- wards. Occasionally at the extreme tip of the gall the leaves open out a little, as in S. strobiliscus n. sp., but without projecting from the tip as in that species. Easily distinguished from that gall by the portion of each leaf which lies "to the weather," towards the base of the gall, not terminating in a rectangular point, but describing a circular arc. The leaves are also more densely pubescent, especially the portion that lies " to the weather." Appears early in the summer and is full-sized by the middle of July, at which time that which is reddish brown in the dry gall is greenish white. The pubescence on the leaves retains its glaucous-white color to the last, except where they are badly weather- beaten. On the same bush throughout the summer may be seen the old, dry, last year's galls, and the young growing galls of the current year. I have already referred to the Orchelimum eggs often found under the scales of this gall. In one gall examined this autumn I counted no fewer than 71 of these eggs. In September I detected a species of Xiphidium, which according to Mr. Uhler is undescribed, ovipositing in the pith at the tip of a broken stem of Goldenrod (Solidago). Probably Locusturiae Latr. (=Gryllidae Leach) do not so generally oviposit in the earth as authors have hitherto led us to believe. 


externallink: https://www.biodiversitylibrary.org/item/23810#page/602/mode/1up
description:
  S. strobiliscus. n. sp. 

  On S. rostrata [bebbiana], a high northern willow not found near Rock Island. I only know this species from a single dried and mature specimen received from Mr. Bebb. and gathered in Winnebago Co., on the extreme northern border of Illinois. It has a diameter of .70 inch and differs from S. strobiloides O. S. 1st. In the tips of all the leaves on the outside of the gall, and not merely those towards the tip of the gall, being angulated not rounded. 2nd. In their external surface not being so strongly pubescent, especially the portion lying "to the weather." 3rd. In the leaves at the tip being almost linear or parallel-sided instead of oblanceolate, and proportionally about 1/2 longer so as to project in a kind of beak from the tip of the gall. 4th. In the tip of the gall being more open than is usual in S. strobiloides. 5th. In the veins even on the inside of the leaves being subobsolete. The cocoon, as far as can be judged from what remains of it, was similar to that of S. strobiloides, but unfortunately it contained, not the larva or pupa of the Cecidomyia, but a parasitic Callimome, which infests several of these Gall-gnats, in the imago state. Hence, and from the fact of there being catkins in flower on the twig on which it grew, we may know that the specimen was about 10 or 11 months old when gathered. As usual in mature S. strobiloides, the twig on which it grew had been killed immediately below it for the space of h an inch or so. Since it might possibly have been the case that it was this species, and not my S. strobiloides, which was named strobiloides by Baron Osten Sacken, as he merely describes his gall as being "in the shape of the cone of a pine and an inch or more long," I communicated to him the distinctive characters between the two species, and he has been kind enough to inform me that my S. strobiloides is identical with his. The specimens which he originally used were obtained in Northern Illinois, and he tells me that he afterwards gathered a single one in Massachusetts, so that we know of this one gall, at all events, that has a wide geographical range. 

  Larva, pupa and imago unknown.


externallink: https://www.biodiversitylibrary.org/item/23810#page/603/mode/1up
description:
  S. gnaphalioides, n. sp.

  On S. humilis.

  A monothalamous, small, solitary, oval or sometimes subspherical gall, ,23 — .55 inch long and .14 — .60 inch in diameter, almost always growing at the tip of a twig and without any side-shoots around it, very rarely from the side of a twig from a small side- shoot no longer than itself, sometimes porrect but oftener with the last inch or so of the twig on which it grows curved downwards, or angularly bent down- wards, or coiled 2 or 3 times round like the tendril of a vine. The leaves composing it are imbricate, sometimes more or less loosely appressed, (when it resembles somewhat the little lemon-yellow garden-flowers known as "everlastings" or ''immortelles" or the indigenous Gnaphalium polycephalum,) but more usually opened out towards their tips, and always with their extreme tips more or less pinched together so as to form a kind of beak and frequently reflexed. These leaves are all entire, sessile, pale green in the summer and in the autumn of a pale reddish brown or pale yellowish brown color with fine, appressed, whitish pubescence on their external surface, and they have a few in- distinct longitudinal veins but no normal midrib and side veins as in S. rhodoides. At the base of the gall they are small and orbicular, then larger and orbicular, then oval, then towards the tip of the gall elongate-oval and elongate-obovate, the tip of the leaf in each case taper-pointed in an angle of about 80° so as to form the beak before spoken of. In the inside they become linear- lanceolate and envelop the central cell as in the preceding species. Described from 72 specimens. Attains its full size by the end of July, and is quite common near Rock Island. Illinois. In two or three cases where the potato-like gall S. batatas n. sp. grew at the tip of a twig, I have noticed the gall S gnaphalioides growing sessile from near the tip of the other gall, evidently from one of the buds included in it. In November I have observed that many of these galls have the larva picked out of them, evidently by birds, and in February full I of them are thus emptied, the leaves of the gall being pecked off on one side. This does not occur with the allied galls S. brassicoides, S. strobiloides, and S. rhodoides, probably because the larva is there concealed and protected by a much thicker wall of leaves; but I have repeatedly in the winter noticed the same thing of the large, spongy gall of the Dipterous Trypeta solidaginis Fitch. Easily distinguished from its five allies by its much smaller size. From S. brassicoides it is also distinguished at once by its always being solitary; from S. strobiloides by the tips of the leaves that lie "to the weather" being not rounded but angulated and beaked; from S. strobiliscus by the tips of the leaves being generally opened out and recurved, and always beaked; and from S. rhodoides and S. coryloides by all the leaves being sessile, instead of the terminal leaves, and in the latter case almost all the leaves, having peduncles. 


externallink: https://www.biodiversitylibrary.org/item/23810#page/606/mode/1up
description:
  S rhodoides, n. sp.

  On S. humilis

  A monothalamous gall like an elongated rose, always growing singly on the tip of a twig, porrect, its general outline elongate-spherical, occasionally spherical and rarely short-spherical, .90 — 1.80 inch long and .70 — 1.90 inch in diameter, never with any twigs, however small, growing round it from the same stem. The leaves composing it are slightly pubescent, entire, with the midrib and branching side-veins very conspicuous, and are almost always opened out and with their tips recurved and occasionally at the extreme tip a little pinched together, but in a few cases they are loosely appressed except at the tip of the gall. The basal ones are small, the following ones larger, all sessile and heart-shaped with the basal lobes of the heart squarely truncate and the tip almost always taper-pointed in an angle of 70 — 80°; towards the tip the leaves become smaller and gradually more and more peduncled, till at the extreme tip the peduncle is generally twice as long as the leaf itself. Inside the gall the leaves suddenly become linear-lanceolate and gradually straighter as they approach the centre, till they finally embrace the lanceolate central cell precisely as in S. strobiloides. Sometimes the peduncled leaves at the tip protrude from the gall as the stamens and pistils of some flowers protrude from the corolla. 

  Described from 15 galls freshly gathered in November, and 50 — 70 gathered in July. Very common in Rock Island County, Illinois. This gall arrives at its full size by the middle of July, when the outside leaves are externally palish green, often changing towards the tip of the gall to pale yellowish green slightly tinged with ro.sy and externally more or less glaucous. In the autumn the leaves become pale greenish brown with a slight whitish pubescence externally, and, after hanging on the twig over a year, almost black.


externallink: https://www.biodiversitylibrary.org/item/23810#page/608/mode/1up
description:
  S coryloides n. sp.

  On S discolor?

  A very large and loosely expanded, monothalamous gall, resembling at a distance a bunch of hazelnuts in their natural husks, growing singly at the tip of a twig without any shoots surrounding it. porrect, its general outline spherical, sometimes elongate-spherical or short-spherical, 1.76 — -2. .35 inch long and 1.95 — 4.10 inch in diameter. The leaves composing it are on the outside large in proportion to the size of the gall, so that some of the middle ones are occasionally two inches across, free from pubescence except sometimes on their external base, entire, with the normal midrib and branching side-veins distinct, and are all of them very much opened out and recurved, the basal ones the most so, so that the latter often touch with their tips the twig on which the gall grows. The basal leaves are orbicular-ovate or ovate, only slightly smaller than the middle ones ; the middle ones are ovate, and both basal and middle ones have their tips tapering regularly in an angle of about 80° — 90°, not taper-pointed in an angle of 70° — 80° as is generally the case in S. rhodoides ; and their base describes an angle of about 90°, instead of being squarely and widely truncate, as in S. rhodoides, and even on the extreme base of the gall generally has a short peduncle nearly 1/8 as long as the leaf itself, which in each successive leaf gradually becomes longer as the tip of the gall is approached, when it is about equal in length to the leaf, which has now become oblanceolate. On the inside, the leaves suddenly become straight, porrect, and very much smaller, and are elongate-linear with their tips tapered to a very acute point, closely appressed, and gradually smaller, till they finally embrace the lanceolate central cell. In the autumn the leaves of this gall are dark reddish-brown, externally with a slight whitish bloom; at other seasons it is unknown to me. 

  Described from 4 specimens. Very near S. rhodoides, which occurs on a totally different willow, but sufficiently distinguished by the characters specified in the description, as well as by its average size being just double. One of the above 4 galls had the heart eaten out by some lepidopterous larva; and adhering to the leaves of another was the pupal integument of a Lepidopteron, much larger than any of those commonly bred by me from the allied galls. All of them, as is very generally the case in this group of galls, had many of their leaves eaten into by Lepidoptera. and contained much Lepidopterous "frass" or excrement.

  I know but three Willow-bushes near Rock Island which can be re- ferred to S. discolor. One of them, a $ . of which I forwarded to Mr. Bebb the inflorescence, was pronounced by him to be certainly S. discolor ; it was from this one that I obtained the galls, which for the present I refer to S. batatas and S. siliqua. Of the second, also a female, I forwarded nothing but the fruit, and Mr. Bebb referred it doubtingly to S. discolor, but thought it might possibly be S. eriocephala. I have carefully compared foliage, twig and bud in these two, and have little doubt they are identical. At all events their very robust, vigorous twigs, tinged with purple and covered with whitish pulveruiescence, so as strongly to recall those of many varieties of apple-tree, and the large buds which have commenced opening out even as early as the last of November, effectually distinguish both, even in the winter time, from the 4 other species of Willow found near Rock Island. The third bush was not discovered by me till the last of November, and agrees so perfectly in all the above characters with the one which is undoubtedly S. discolor, as well as in the foliage, some of which still adhered to its twigs, that I have little hesitation in referring it to the same species. I observed however on its main limbs large blotches or wide bands of whitish-gray, which could not be seen on either of the other bushes. In any case the inflorescence next spring will definitively decide the question of its specific identity with S. discolor. It was on this last that I found the galls C. coryloides ; the second bush bore no galls at all.


externallink: https://www.biodiversitylibrary.org/item/23810#page/610/mode/1up
description:
  S. cornu

  On S humilis

  A lateral bud deformed into the shape of a monothalamous. very elongate, slender, cylindrical, tapering, hollow, rigid horn, very slightly pubescent, of a very dark reddish brown color when mature, and with about 12 or 14 longitudinal, pretty regular striae like a coleopterous elytrum. This gall is .30 — .77 inch long, .07 — .10 inch in diameter at base and .05 — .07 inch close to the tip. where for the length of about .10 inch it is flattened and moderately pubescent, and at the extreme tip, which is rounded, opens by a terminal slit. Sometimes it is solitary, sometimes 2 or 3 of them, or even as many as 10, grow at irregular intervals on a small twig 4 inches long, with a few of the intervening buds in their normal condition. Generally it is perfectly straight, diverging upwards from the twig at an angle of 15° — 35°, but occasionally it is a little bent in the middle, and occasionally it curves backwards in a regular curve, so that in one instance the tip nearly touches the base. When cut into, the walls of the hollow are seen to be no thicker than stout paper, but very stiff and hard, and on the terminal 1/2 the internal surface is pretty smooth with indistinct longitudinal rugae, except the terminal .05 inch, which is armed with very long, whitish pubescence directed obliquely forwards. In the basal 1/2 of the horn lies the cocoon, which is closely agglutinated to the walls of the cell except at its tip, where it forms a filmy, whitish diaphragm as in S. siliqua n. sp. ? The cell formed by the hollow of the de- formed bud is prolonged into the woody origin of the bud for .10 — .15 inch, but the twig itself is not swelled or deformed, as it is in the allied polythalamous gall S. triticoides n. sp., further than by a slight and scarcely noticeable intumescence at the origin of the bud. 

  Described from 8 living specimens on four different twigs and 10 old dead and dry specimens all on one twig, the whole gathered in November. Out of the 18. 6 or 7 had been bored laterally by some minute parasite, and from at least two of the recent ones parasites had perhaps escaped at the terminal slit, for they contained neither larva nor cocoon, and were unbored, although one of the recent ones was bored. Rare near Rock Island, and difficult to discover from its simulating a short, lateral twig. When these galls occur in great numbers on a twig, the intervening buds perish, but when there are only one or two of them, they do not. When the twig is .08 inch or less in diameter, the part of it which lies beyond the galls shrivels up and perishes, even if there be only one of them, but when the diameter is .13 or over and there is but a single gall, it survives, at all events till the next season.


externallink: https://www.biodiversitylibrary.org/item/23810#page/611/mode/1up
description:
  S siliqua n. sp.?=Salicis? Fitch=rigidae? Fitch, OS

  On S humilis (and also on S cordata? and S discolor?)

  A monothalamous, solitary, oval or subspherical. woody gall, .55 — 1.00 inch long and .20 — ..34 inch in diame- ter, growing at the tip of a twig, frequently with several twigs apparently of the same year's growth surrounding it, tt pared at tip to a short, blunt, tubiliform beak, which is evidently a deformation of the terminal bud, and hollow inside. The outside surface of the gall, which is the natural color and texture of the bark of the twig, always contains, besides the terminal beak-like bud, 2 — 5 buds, which are still alive in November in the recent gall but afterwards perish along with the gall itself, as does also, unless the twig on which the gall grows be large, a portion of that twig. Sometimes one of these external buds sprouts out into a twig, growing from the outer surface of the gall, and in a single spe- cimen there are four such twigs. The walls of the internal cell or hollow, in- cluding the bark, are .06 — .11 inch thick, and lined when mature inside with the cocoon of the gall-maker, which is detached and of the usual delicate texture towards the tip of the hollow, so as to form a kind of diaphragm to exclude any air that might enter through the terminal beak, but is agglutinated strongly to them everywhere else, though it may be detached piece-meal, generally with a thin layer of the greenish woody matter adhering to it. The internal surface of the terminal beak is smooth, continuous with that of the main c. 11 or hollow, and not strongly pubescent at tip as in <S'. cornu ; on its external surface there is the natural suture at its base. In one specimen, where a large, abnormal, woody wart had been formed about the middle of the hollow, the larva, instead of including the wart in his cocoon, had had the remarkable foresight to con- struct his cocoon entirely above the wart, and was thus compelled to make another diaphragm just above the wart, besides the usual one near the beak, and to lie in a much smaller compass than usual between the two. Described from 10 living- specimens and 27 old and dead ones, all from S. humilis. Rather rare near Rock Island. Varieties of S. ha- tatas n. sp. occur, which externally can scarcely be distinguished from «S'. siliqua ; but on cutting into them they are seen to be not hollow, but filled with a spongy substance containing several of the cells which are inhabited by the Cecidomyia of that polythalamous (xall; and more- over, the terminal bud is not beak-like and tubiliform. Specimens found on S. cordata in November differ as follows: — \st. The average dimensions are about i smaller, the length in 4 living spe- cimens and 41 dry and dead ones being .45 — .85 inch and the breadth .17 — .28 inch. 'Ind. Out of three of the living galls where the Ceci- domipa was present, there was in two a double diaphragm both at top and bottom of the hollow, instead of the single diaphragm at the top only; but in the other one the diaphragm was single and normal, 'ird. The number of buds on the external surface of the 45 galls is 1 — 3 in- stead of 2 — 5. \t]i. The terminal beak in i of the above 45 specimens is conspicuously recurved, whereas it is never recurved in those that grow on 8. humilis, thovigh it is sometimes a little oblique and in a single specimen is at right angles to the axis of the gall. A gall found August 1 had the beak so much recurved as to touch the side of it, like the tongue-case of the pupa of vSphinx 5-maculata Haw. — From my having in two successive seasons found the old dead and dry galls on both the above two willows at least 8 or 10 times as numerous as the green ones, and from the very weather-worn appearance of many of them, and the fact that a few of them were overgrown and almost obli- terated by the twigs that surrounded their base, I infer that they hang on the twig for several years. A single living gall gathered on S. discolor in November differed from the living ones found on S. humilis as follows: — Is^. The woody matter composing the outer shell is much thinner than in any one of 14 green specimens off S. humilis and 3 green specimens off S. cordata that I have cut into, being to a much greater extent medially interrupted by a layer of brown spongy matter, so that the gall was rather crushed by the knife than cut by it. 2.nd. Instead of the external surface being phimp and of the natural texture of the bark of the twig, it was strongly rugose, when recently gathered, and had much the color and texture of a completely withered blue plum. This does not occur in green specimens found at the same time of the year on the other two Willows, though it is often seen in the old dry ones. — Length 1.00 inch, diameter .80 inch, external buds 3. One specimen.


externallink: https://www.biodiversitylibrary.org/item/23810#page/618/mode/1up
description:
  S triticoides, n. sp.

  On S cordata [eriocephala?]

  A polythalamous, woody gall .70 — 1.23 inch long and .30 — -.37 inch in diameter, bearing a remote resem- blance to a head of wheat with the kernels elongated, naked, pointed and very protuberant, its general outline oval or elongate-oval, and formed by the swelling of a twig to 2 or 3 times its former diameter, the swelled portion being very much contracted longitudinally, so as to bring each kernel-like bud nearlv or quite into contact with the base of the one that precedes it in the same row. the whole number being arranged in 4 irregular rows. Besides the swelling of the twig itself, the origin of each bud is also swelled into a more or less large tubercle, inside which is excavated longitudinally a cylindrical, slightly ru- gose and moderately polished cell, .25 — .27 inch long and .06 inch wide, the bud itself being elongated to about .17 inch and deformed so as to become a beak- like, tubiliform continuation of the cell, without any suture on the inside inter- vening, moderately polished inside like the woody part of the cell, and without pubescence as at the interior tip of the cell of 8. cornu n. sp. Through a slit at the tip of this beak-like bud the maker of the gall escapes, while, as usual, the parasite that preys on the gall-maker bores through it laterally. Above the gall the twig generally shrivels to about J its natural diameter, but occa- sionally where there are only a few cells — say 7 or 8 instead of 15 or 16 — it is not very materially diminished in size.— Described from 3 dead and dry speci- mens. Very rare near Rock Island. Larva, pupa and iMA(iO are all unknown; but from the structure of this gall being so exactly like that of *S'. siliqua n. sp. '( and espe- cially aS. cornu n. sp., there can be no doubt that it is. like those two galls, the work of a Cecidomijia . Inside several of the cells I found cocoons similar to those of C. s. strohiloldes. &c.. but much longer in proportion to their diameter, and not glued to the walls of the cell as in S. siltqua and *S'. cornu, so that I was able after relaxing the gall to extract two of them entire. They measured when extracted .42 — .44 inch in length and .06 inch in diameter, thus occupying the entire length and breadth of the cell including the beak formed by the bud. In the bottom of many of these cells, where the beak-like bud was bored laterally, I found an empty cocoon very similar to that of a parasitic Proctotrupide which occurs in the imago state in November in the central cell of aS^. strohiloides O. S. ; and in these cells there was no Cecidomyidous cocoon, as is also sometimes the case in the cells of C. s. strohiloidea that are occupied by the above Proctotrupide. 

  S hordeoides n. sp

  On S humilis

  This gall has some resemblance to a beardless ear of four-rowed barley, and differs as follows from S. triticoides : — 1st. The twig on which the cells are placed is not materially enlarged and is of a uniform diameter throughout. ^Ind. The twig is abnormally shortened as in S. triticoides, but only so that the tip of each deformed bud touches or nearly touches the base of the one that succeeds it in the adjoining row. instead of the base of the one in the same row. 3rr7. The entire cells ai*e only .20 inch long, instead of .42 — .44 inch, and they extend only .05 inch, or \ of their entire length instead of 3-5ths of their entire length, into the woody origin of the bud, the deformed buds being not much elongated, but hollow and. as well as the woody part of the cell, polished internally. Ath. The woody origin of the buds is scarcely swelled and protuberant. — Described from one dead and dry specimen, 1.40 inch long and .10 inch in diameter. It contains 10 deformed buds, regularly arranged with no undeformed ones intervening, as is the case in the monothalamous gall S. cornu, when several of them grow near each other. As in some S. triticoides. the tip of the twig has completely shrivelled up and per- ished. Easily distinguished from the monothalamous, Tenthredinidous gall, S. gemma n. sp., which occurs on the same Willow, by there being no normal buds between the affected buds, and by the buds themselves not being abnormally swelled out laterally, and being hollow, not solid, inside. But for the fact of several of the deformed buds having been bored by minute parasites, I should never have suspected this specimen of being what it most undoubtedly is — a true Cecidomyidous gall ; and but for its strong homologies with S. triticoides. I should hesitate whether to consider it as a congeries of solitary galls, like aS'. cornu. or a true polythalamous gall, where the twig itself is swelled and deformed and converted into a gall, like S. triticoides. It must be very difficult of discovery, when it is recent and the cells are unbored by any parasites. Larva, pupa and imago unknown.


externallink: https://www.biodiversitylibrary.org/item/23810#page/619/mode/1up
description:
  S nodulus, n. sp.

  On S longifolia [interior]

  A small, monothalamous, woody gall, sometimes terminal but generally not so, scarcely ever including any buds, growing on twigs .05^.15 inch in diameter, variable in shape, but generally consisting of a mere oval enlargement of the twig to half as large as its normal size for the length of .20 — .50 inch. The surface of the enlargement is either the usual color of the bark, or simply discolored and dark, or a little roughened with brown scales and longitudinally sinuate and interlacing stria. Occasionally it assumes the form of an elongate, lateral, bunnion-like swelling about .27 inch long and .1.3 inch wide, as in some varieties of S. batatas n, sp., and in one specimen there occurred an intermediate grade between this variety and the normal type; occasionally it grows at the base of a very small side- shoot, when the tip of the side-shoot shrivels up and perishes ; and occasion- ally the growth of the side-shoot is completely arrested, and the gall becomes a mere obhemispherical swelling about .20 inch in diameter, with its upper sur- face in an irregular plane, and very rugose and brown, located at the spot where normally there ought to be a bud. On cutting into this gall in Novem- ber, it is found to contain a single cell — smooth on the inside when the gall- making larva is present, but, as in ^S". batatas, without any separate cocoon — and much reddish-brown matter where the larva had formerly burrowed, and occa- sionally some grass-green soft matter: but the external walls are still in their normal white, ligneous state, the larva having apparently confined itself to the pith and the wood immediately surrounding the pith. Described from 9 specimens. Rare uear Rock Island. Externally this gall cannot be distinguished from the smaller varieties of C. bata- tas, but the former is monothalamous, the latter polythalamous ; neither can it be distinguished, except by its much smaller size and its much smaller cell, from the Tenthredinidous gall G. nodus which grows on the same willow. Of the 9 galls examined, 7 were unbored, 3 of which contained each a single larva of Oec. s. nodulus, 1 a single hairy Chalcididous larva, probably a Callimome, 1 a single Curculionidous larva, no doubt an Inquiline. and in 2 the gall-making larva was absent and must have perished in early life, for although its work was plainly visible yet the gall was not bored. In none of the 9, whether bored or un- bored, had the twig been killed, except in the very small gall before referred to, where the terminal bud had sprouted out into a minute shoot which afterwards perished. The smallness of this larva and there being only one in each gall, readily account for this otherwise anoma- lous fact. I found Dec. 1st in one of these galls, which had been bored by a single hole and contained no Cecidomyidous larva, a minute Lepidop- terous larva, doubtless an inquiline, and over a dozen small and young Aphis, which had probably taken refuge there for the winter. May not Hartig have been deceived by some such case as this into suppos-ing, that certain European Willow-galls were the work of Aphis ? (See above, p. 551.) On July 31st I found a bored and empty specimen of the Tenthredinidous gall C. pomum tenanted in the same manner by over a dozen Aphis.


externallink: https://www.biodiversitylibrary.org/item/23810#page/621/mode/1up
description:
  S batatus n. sp.

  On S humilis (S cordata? and S discolor?)

  A polythalamous gall of very variable shape and size, pale green when young, the color of the bark when mature, growing on twigs .06 — .19 inch in diameter, almost always some distance from the tip of the twig. Sometimes it resembles a small kidney-potato pierced lengthways by a twig, and has then most generally a smooth, polished surface studded with a few buds, one or two of which occasionally give birth to a shoot, and it then reaches 1.35 inch in length and .60 inch in diameter. Sometimes it resembles a young apple pierced lengthways by a twig, and it then attains a diameter of .50 inch. Sometimes it forms a hemispherical or hemielliptic swelling, like a bunnion, on the side of the twig and attains a diameter of .30 inch. Sometimes all these different shapes are strung together one after the other in more or less close proximity, on the same twig. Sometimes it is reduced to a small, elongate-oval enlargement of the twig for 1/2 or 3/4 an inch ; and occasionally it becomes so irregular and so full of side-shoots, bulges, cracks, roughnesses and lobes, as to defy description. Very rarely it is terminal and assumes the form of S. siliqua, but may be distinguished by the terminal bud not being elongated and tubiliform, and by being solid and not hollow inside. On one occasion I found what had evidently been a S. siliqua gall, occupied laterally by spongy matter containing 4 larvae undistinguishable from those of C. s. batatas, the elongated cell of the larva of C. s. siliqua being still in existence but contracted in diameter and empty. When these galls assume the elongate bunnion-like form, they are undistinguishable externally from the Tenthredinidous gall S. ovum, which occurs on S. cordata. and S. ovulum, which occurs on the same willow as S. batatas, but may be distinguished on cutting into them by the fibres being linear and radiating from the twig, whereas the other two galls are composed of a series of spongy lamellae at right angles to the axis of the twig, and moreover, when laid open to their base, ex-hibit the longitudinal slit made by the ovipositor of the mother Saw-fly. The smallest galls above referred to are only .15 inch in diameter; but there is a regular gradation from these to the larger and more conspicuous forms, and by isolating a number of the first in a separate breeding-jar, I ascertained that they produced the same Cecidomyia (7 specimens April 7 - May 10) and the same 3 parasites, viz. 2 Chaleidides and 1 Proctotrupide. When cut into about the last of July, the interior of this gall to the depth of .07 — .10 inch from the surface, is found to be white and fleshy; when cut into in the autumn or early in the spring, the substance of all but the very smallest, which are almost entirely woody and whitish, is found to be reddish-brown and of a dense, spongy texture, with indistinct fibres radiating from the twig. Some little distance from the external surface there are at this time a number of cells, about § of them tenanted by white, parasitic larvae, some hairy and some glabrous, be- longing to the Chalcididous genera Callimome and Decatoma (?), and about J of them tenanted by the orange-colored larvse of the Gall-gnat which originates the gall. In 3 or 4 instances I have seen the gall S. gnaphalioides growing sessile from the tip of (S. batatas. — Described from 100 — 150 specimens. Very com- mon near Eock Island on S. humilis. In galls similar to the last mentioned, small, elongate-oval galls, but growing on S. cordata. I found May 9 a larva undistinguish;ible from that of C. s. batatas and with the same breast-bone, but did not suc- ceed in breeding the perfect Grall-gnat. though I obtained many Chal- cidiffpe from these galls identical with two species bred copiously from S. batatas, one of which — a Decatoma ('^) with spotted wings — has hitherto occurred in no other gall, though a similar species infests Ci/- nips q. spongifica and other gall-flies. In November I found on *S'. discolor 8 galls, apparently identical both externally and internally with the iS. batatas found on S. humilis, 8 old and dry ones of the normal form which were all bored and strung along on the same twig, and 5 green and recent ones of the lateral, bunnion-like type on two diffbrent twigs. Their diameter was .19 — .40 inch. From the recent ones I obtained 6 larvae, which when compared with 6 taken from galls on S. humilis differed in no respect. In the preceding spring I had obtained 2 or 3 similar galls of the bunnion-like type from the same bush, from which I bred a large Microijaster, whence I infer that some lepidopterous larva had been living as an Inquiline in one of them, as the parasite was much too large to have lived in the body of C. s. batatas, and besides I have met with no instance of Ich- neumonidous insects being parasitic on Cecidomyia. I found at the same time several galls on the same bush, which, as has been stated to be sometimes the case in >S^. batatas, assumed the form of a slight, elongate-oval enlargement of the twig; but from these I bred nothing. < )n the whole, further investigation will be required to determine, whe- ther tbe imago produced from these galls on S. cordata and S. discolor is identical with Cec. s. batatas. It is rather singular, that in these »S. discolor galls I found no larvae at all of the Decatoma (?) and Calli- mome, which so greatly outnumber the larvae of C. s. batatas in the S. humilis galls. It is worth remarking, that the only two Cecidomyidous galls which appear to grow on more than one species of our Rock Island Willows — viz. aS'. batatas and C. siliqua — occur on as many as three species of them, and that these three species should in both eases be the samf", three, viz. S. humilis, S. cordata and S. discolor. The chances are very greatly against such an event happening, without some good and suffi- cient cause for it. Mr. Bebb informs me that there is a close alliance between S. humilis and S. discolor; but that neither S. cordata (=S. rigida) nor S. lucida is allied to the first two. While on this subject I may say that Mr. Bebb has re-examined the doubtful species of Wil- low referred to above (p. 546), and has concluded that it is certainly neither 8. nigra nor S. alba, and that it is not improbably S. fragilLs Lin., a species which has been introduced into N. A. from Europe. 


externallink: https://www.biodiversitylibrary.org/item/23810#page/626/mode/1up
description:
  S verruca, n. sp. 

  On S humilis.

  A small, monothalamous, irregularly spherical, greenish yellow gall, .07 — .13 inch in diameter, growing the latter end of August from the midrib or some of the principal veins of the leaf, half of it projecting from each side of the leaf. The upper side is flattish or with a minute point or nipple, the lower side branches out into a ragged, wart-like excrescence, whence the specific name, which later in the season bursts open so as to afford an exit to the insect. When cut into in August, the external wall of a few galls is found to be rather woody, enclosing a central cell, in which lies the larva; but the majority of them-are still solid. From 1 to 12 are found on a single leaf, several of them being often confluent, but with their internal cells, when they have any, separated by a thin partition, and with separate warts to each on the under side of the leaf, which afterwards open separately. 

  Rather abundant, but local near Rock Island. Described from 38 affected leaves. 


externallink: https://www.biodiversitylibrary.org/item/23810#page/626/mode/1up
description:
  S semen, n. sp.

  On Salix nigra

  A minute, monothalamous, hollow, irregularly hemispherical, greenish yellow gall, .02 — .04 inch in diameter, mostly on the upper side of the leaf, and often, but not always, with a pointed nipple on the middle of the hemisphere, always with a corresponding circular depression on the other side of the leaf, in the middle of which is a very minute, flattish hemisphere. Very frequently on one and the same leaf the position of the gall is reversed from the ujjper to the lower side, as in Q. pihiloe Walsh. On a single leaf scores of them may often be counted, generally with several masses among them, composed of two or more confluent galls. Commences its growth early in the summer, and by the last of August many are found to be burst open at top, yet at the same time very many of them, when opened, are found to be solid without any central cell. By November most of the galls from which I attempted to breed the insect had burst open into a ragged, wart- like shape on the hemisjiherical side, but no larvte had escaped from them and none were discoverable in them. As the leaves were kept too moist, so that they moulded badly, the larvae had probably perished in the galls. Described from 20 affected leaves. From its close homology with the much larger oak-galls St/mmrtrk-a 0. S. aqd Q. pilulse Walsh, iu the former of which Cecidomyidous larvae were detected by Osteu Sacken, and described (Dipt. X. A. p. 201) as having a Y-shaped breast- bone, and in the latter of which I found myself, September 14th, several orange-colored larvje, which, from the presence of a clove-shaped breast-bone, were undoubtedly Cecidomyidous, and from the fact of a similar leaf-gall on a Willow, *S'. verruca n. sp., being inhabited by a Cecidomyidous larva, there can be no doubt, I think, that the gall S- semen is the work of a Grall-gnat. Prodigiously abundant and very common everywhere in Rock Island County, Illinois, on the Black Willow, the foliage of whole trees being thickly frosted over by it, so that the leaves look like nutmeg-graters. I have in a cursory manner noticed in July several specimens of what seemed a very similar gall ou S. discolor, but found no larva) in them ; and in a single instcince I found, August 20, two leaves of S. longifolia on a twig which grew out of a bunch of the galls S. brassicoides, covered so densely with some- what similar galls as to be intermediate in appearance between S. se- men and *S'. penigma. On August 29 I discovered in one of the cells of this gall a minute, pale-colored, apod larva with a large, scaly head, and the disk of its dorsum, but not of its venter, fuscous. This so ex- actly resembled a much larger larva of which I have found many spe- cimens in the Cecidomyidous gall, Q. pilidx Walsh, and which I am sure, from comparing it with the larva of Anthonomus scutellatus Schonh., must be Curculionidous, that I believe it to be also Curculionidous, and inquilinous, like the othei* larva, iu the gall where it occurred. I have noticed towards the last of August galls about the size of the head of a large pin. similar to S. semen, and often similarly confluent, o'rowino- in con.siderable abundance on the leaves of the River Kirch (Betula nigra), chiefly or almost entirely on their upper surface. And on the leaves of the Button-bush (Cephalanthus) I have noticed at the same period of the year galls of the same character, in the same luxuriant profusion as S. semen occurs on the Black Willow, whole bushes being covered with them ; but in neither of the two kinds could I discover any larvae. I believe them both to be the work of Cecidomyia. It does not follow, because all these galls are so small, that therefore their Gall-gnats must be abnormally small. The gall S. rhodoides n. sp. is about 4 times as long and wide as the Grail S. gnaphalioides n. sp., yet the Gall-gnat produced from the latter is only \ shorter than the (rail-gnat produced from the former. Larva, pupa and imago unknown. 


externallink: https://www.biodiversitylibrary.org/item/23810#page/628/mode/1up
description:
  S aenigma, n. sp.

  On S nigra

  A polythalamous, crumpled, irregularly spherical or ellipsoidal mass, something like the aborted mass of flower-buds of a common cauliflower, but with a more ragged and uneven surface, .30 — 1.10 inch in diameter, and growing almost sessile or sometimes on a stem as long as .50 inch, which is often branched and much flattened or distorted, from the side or occasionally from the tip of twigs .05 —.30 inch in diameter. When cut into early in the summer, there is seen to be no regular heart or symmetrical arrangement of the parts, as there is in all monothalamous galls, and the stem is crisp and rather fleshy than woody. This gall first appears early in June, being chiefly a deformation of the flower-catkins, but occasionally, unless I was deceived from confounding it with S. semen n. sp., which I think must have been the case, of the leaves. At that time, and for a month or two afterwards, it is of a pale green, but long before autumn it dries up and becomes brittle and of a dark ash-gray color, without, however, losing its original shape, and hangs on the trees till long after the next spring opens. It contains, so far as I could discover, no regular cells, but the larvae of the Gall-gnat appear to burrow irregularly in the main stem and its branches. On the same twig may often be seen 6 or 8 of these galls at irregular intervals of half an inch or U inches, and frequently two of them grow side by side and run together. "Whole trees are sometimes so covered by them, that the galls seem almost half as numerous as the leaves. As usual, the twigs, unless very large, are killed by the presence of these galls shortly after the galls have become mature. 

  Described from 150 — 200 specimens. Very common and abundant everywhere in Rock Island County, Illinois. 


description:
  Salix prolixa chosen as a placeholder host based on [this unconfirmed observation](https://www.inaturalist.org/observations/54119472). 


externallink: https://www.biodiversitylibrary.org/page/3830881#page/234/mode/1up
description:
  S gnaphalioides

  I found a single specimen on a bush of S. discolor growing among numerous S. humilis, on which last willow alone this gall had previously occurred. A very similar gall, but differing in the tips of the leaves not being beaked, was gathered on S. Candida by Dr. Geo. Vasey, in Illinois. I have 8 dried specimens of it from Mr. Bebb. 


externallink: https://www.biodiversitylibrary.org/page/3830881#page/235/mode/1up
description:
  S coryloides

  I have since fouod two additional specimens in a different locality, and as before on S. discolor. Thus, in addition to the occurrence of two very distinct but closely allied bud-galls on the same species of Willow, S. humilis, viz : .S. rhodoides and S. gnaphalioides, we find two very distinct but closely allied bud-galls on the same species of Willow, S. discolor, viz : S. strobiliscus and S. coryloides.


externallink: https://www.biodiversitylibrary.org/page/3830881#page/235/mode/1up
description:
  S siliqua 

  Besides the single one found on S. discolor, I have since found about a dozen others on that Willow, and received through Mr. Bebb over a dozen gathered on that Willow in New Hampshire by the Rev. W. J. Blake. They can only be distinguished from galls found on S. humilis by their uniformly larger size, which may be due to the rank growth of this species of Willow. Mr. Blake also sent me many specimens of this same gall gathered on S. rostrata [bebbiana] in New Hampshire, which were about the same size as those found on S. cordata ; and I have a single dried specimen gathered in Illinois on S. petiolaris by Mr. Bebb. Thus we have what seems to be the same gall growing on six different Willows. S. humilis, S. discolor, S. rostrata [bebbiana], S. cordata, (=S. rigida) [eriocephala], S. petiolaris. and according to Dr. Fitch on S. lucida. I said that the terminal beak of this gall is never recurved in specimens growing on S. humilis; but in 1865 I found one such gall on S. humilis. In those growing on S. rostra ta this is particularly common. It is singular that some galls should be thus found on many Willows, and others apparently be restricted to one species; but the same phenomenon occurs in Cynipidae. In one of the public squares in Rock Island, 111., there grow 30 or 40 trees of the exotic S. alba, and interspersed among them many bushes of the indigenous S. longifolia covered with their peculiar gall, S. brassicoides Walsh. Yet not a gall either of that kind or of any other kind, whether Cecidomyidous or Tenthredinidous, can be seen on the S. alba trees, even on the closest examination before and after the fall of the leaf. 


externallink: https://www.biodiversitylibrary.org/page/3830881#page/237/mode/1up
description:
  S verruca 

  Oct. 11th I found several of these galls on S. discolor, undistinguishable from those found on the closely allied S. humilis. The larva was orange-color with the usual whitish bowel-like markings, .08 inch long, 2.33 — 3 times as long as wide, depressed, with a large head. Breast-bone black, elongate-semi- oval and rather longer than wide. Two specimens. Thus we have no less than 4 species of Cecidomyidous galls common to the two closely- allied Willows, S. discolor and S. humilis, viz : S. gnaphalioides, S. siliqua, S. batatas and S. verruca. 


externallink: https://www.biodiversitylibrary.org/page/3830881#page/237/mode/1up
description:
  S semen

  This is not a Cecidomyidous, but an Acaridous gall, and is constructed on the same principle as 15 or 16 others with which I have become acquainted, all growing on the upper side for the most part of the leaf of various trees, and composed of a more or less elongate sack opening below by a more or less closed aperture, and on its interior surface covered with rough excrescences of different shapes On the other hand, all Cecidomyidous galls known to me are smooth and free from excrescences inside. From most of these Acaridous galls the mites escape through the aperture below, but in some, e. g. Cerasi crumena Walsh MS, on Cerasus serotina, the gall always bursts open above as in Salicis semen. Similar, but not identical, galls are found on several other Willows. On Aug. 25 I found in one of these S. semen galls, which was about .03 inch in diameter, as many as 40 or 50 hyaline-whitish young Acarus, which, as is usual, were much more elongate than the perfect Mite. Hence it may be readily understood how minute their size is, and how liable they are to be overlooked, except under a very powerful lens, especially as, un- like the perfect Mite, they are very dull and sluggish in their motions, which indeed seems to be the universal rule with all the larvae of the (Jail-making Mites. The perfect Mite, which was found on the same day in other galls, is hyaline-whitish with antenuiform front legs as long as its other legs, which front legs it elevates in the air and constantly vibrates up and down as it runs. Those found in galls on other trees differ but little in Bize, structure or color, some species however being spotted. In a few galls, e. g. Crataegi vermiculus Walsh MS, which occurs abundantly both on Crataegus tomentosa and Cr. crus-galli, the larvae of the mite are of a pale pink color.


externallink: https://www.biodiversitylibrary.org/page/3830881#page/238/mode/1up
description:
  S aenigma

  I have little doubt that this gall also is a deformation produced by an Acarus. From its great scarcity in 1866. 1 was unable to examine any green specimens, but on Aug. 27 I found among the crumpled exterior surface of a partly dried-up specimen a half-grown Acarus similar to those found in S. semen. It may be stated that on the tree from which this gall was procured there were no S. semen galls ; for this gall too, as well as S. aenigma, though so exorbitantly abundant in 1864 has been comparatively quite scarce in 1866. Usually in Acaridous galls the larvae live in a hollow inside; but in one on the leaf-stalk of the Black Walnut — Juglandis caulis Walsh MS — they reside among the brown external woolly pubescence, just as in S. aenigma they probably reside in the crumpled external surface of that gall. The Cecidomyidous larva) that I found in June and August in S. aenigma were most likely inquilines. (Proc. etc. III. pp. .608 — 9.) I have received through Mr. Bebb from Cr. W. Clinton, Esq., Buffalo, N. Y., pressed specimens of this gall growing on the same Willow — S. nigra — on which I find it exclusively. Hence there are at least 3 Willow-galls common to the Eastern and the Western States — S. strobiloides, S. siliqua, and S. aenigma.


externallink: https://www.biodiversitylibrary.org/page/3830881#page/262/mode/1up
description:
  S ovum n. sp.

  On Salix cordata [eriocephala]

  An oval or roundish sessile monothalamous swelling, .30 — .50 inch long, placed lengthways on the side of small twigs, green wherever it is smooth, but mostly covered with shallow longitudinal cracks and irregular rough scales which are pale opaque brown. Its internal substance fleshy in the summer like that of an apple, but with trans- verse internal fibres. When ripe in the autumn, filled with reddish-brown spongy matter, with close-set transverse internal fissures at right angles to the axis of the twig. On cutting down to the twig at any time, a longitudinal slit about .20 inch long becomes plainly visible. Particular twigs on badly infested bushes sometimes have one of these galls about on every half inch of their length, and not placed in a regular row, but indiscriminately on any side of the twig. Abundant but local. Described from very numerous specimens. 


externallink: https://www.biodiversitylibrary.org/page/3830881#page/264/mode/1up
description:
  S ovulum n. sp.

  On Salix humilis

  Undistinguishable both internally and externally from S. ovum n. sp. But for the fact that the larvae differ in color, and that, of the five species of willow found near Rock Island, IL., this type of gall occurs only on S. humilis and S. cordata [eriocephala] — two willows which are, according to Mr. Bebb, very distinct — and never, as I have carefully observed, on S. discolor — which is on the same authority, very closely allied to S. humilis, the species on which S. ovulum is found — I should not suppose S. ovulum to be a distinct (phytophagic) species from S. ovum. Possibly, indeed, it may not be so and to determine doubts it is better to await the discovery of male female imago. Besides the three bushes of S. discolor mentioned above, (Proc. Ill, p. 589,) I have since discovered and examined closely several dozens. This gall was rare in 1864 — 5 and 1865 — 6, but common in 1863 — 4. Not local, but generally distributed. Described from 30 specimens.


externallink: https://www.biodiversitylibrary.org/page/3830881#page/266/mode/1up
description:
  S pomum, n. sp.

  On S cordata [eriocephala] (and very rarely on S discolor]

  A smooth, fleshy, sessile, globular or slightly oval, monothalamous gall, re- sembling a miniature apple, .30 — .55 inch in diameter, growing on one side of the midrib of a leaf, and extending to its edge or sometimes a little beyond it. The principal part of the gall generally projects from the under side of the leaf, and only about 1-6th of its volume from the upper side, although very rarely it is almost equally bisected by the plane of the leaf. Scarcely ever more than one gall on a leaf, and very rarely two of them more or less confluent, so as to seem like one kidney-shaped gall. External color greenish-yellow, generally with a rosy cheek like an apple, especially on the upper surface, and often with many dark little dots on its surface. Internal color whitish. The above is the appearance presented July 31 when the gall is fully matured, but as early as May 24 it has nearly attained its full size, and has the rosy cheek very conspicuous. Abundant but rather local. Described from very numerous specimens. As to the occasional occurrence of this gall on S. discolor see under [No. 21 bis.](https://www.gallformers.org/gall/3549) An analogous gall is formed in Europe on the leaves of various kinds of willows by Nematus gallicola Westw.


externallink: https://www.biodiversitylibrary.org/page/3830881#page/269/mode/1up
description:
  S pisum, n. sp.

  On Salix discolor

  A subspherical, pea-like, hollow, pale yellowish-green gall, always growing on the under side of the leaf. and almost always from one of the side-veins, very rarely (1 specimen) from the midrib, and attached to the leaf by only a minute portion of its surface, .18 — .28 inch in diameter, and a few, which were probably immature or abortive, only .08 inch in diameter. Almost invariably there is but one gall to one leaf: but on 4 leaves there were two, and on 2 leaves three of them, and occasionally two are confluent. The surface of the gall is without pubescence, in some smooth and even, in others a little shrivelled, generally studded in the medium-sized ones with 4 — 12 small, robustly conical nipples, which in the larger ones have hurst into a scabrous brown scar. Only in 3 out of 62 galls was there any rosy cheek, as in S. pomum. The point of attachment is marked on the upper side of the leaf by a brown sub-hemispherical depression about .04 inch in diameter. Abundant but local. Described Aug. 25 from 62 freshly-gathered galls. At the time the 1st part of this Paper was published I was unacquainted with this gall, which accounts for the irregularity in the numbering, (21 bis.) 

  On the same bush with the above there occurred 13 galls, mostly unbored, so identical in appearance with S. pomum that I did not think it worth while to attempt to breed from them. On Oct. 14, out of another lot of S. pisum on another bush of S. discolor, I found that about one-fourth to one-fifth had a slightly rosy cheek. On this bush also I met with 4 S. pomum in company with S. pisum. but all empty and bored, but whether bored by the Gall-maker or by the inquilinous Anthonomus sycophamta. n. sp. (Coleoptera) is uncertain. In both the above two cases a few S. discolor bushes were growing in the midst of very large numbers of S. cordata [eriocephala], the species on which S. pomum is normally found. This gall is evidently allied to those produced by the European Nematus intercus and N. gallarum, which are described as "globose, spongy, pedunculated galls along the mainrib of the leaf;" but it differs in growing, not exclusively from the mainrib, but indiscriminately from any of the veins. Distinct from S. pomum by its being peduncled not sessile, and by its smaller size and the general absence of a rosy cheek, and from S. desmodioides by its short peduncle and by its very different shape. 


externallink: https://www.biodiversitylibrary.org/page/4885236#page/304/mode/1up
description:
  Eriophyes salicicola

  One or two narrow, longitudinal, yellowish green or brown upward folds opening below, on Salix longifolia [interior]


externallink: https://www.biodiversitylibrary.org/page/4885236#page/304/mode/1up
description:
  Eriophyes sp.

  Small thickenings or inrollings of the leaf margin, green, scattered or coalescent, on S alba


externallink: https://www.biodiversitylibrary.org/page/4885236#page/304/mode/1up
description:
  Eriophyes sp.

  [Salix exigua added as a placeholder]

  Irregular, more or less crenulate midrib fold, length 7 mm. Utah. 


externallink: https://www.biodiversitylibrary.org/page/4885236#page/304/mode/1up
description:
  Eriophyes sp.

  Small, irregularly, serrate, roughened, pocket galls or semicapsules, green or red, usually on upper surface on Salix alba, balsamifera [pyrifolia], discolor, and rostrata [bebbiana].


externallink: https://www.biodiversitylibrary.org/page/4885236#page/304/mode/1up
description:
  Eriophyes sp.

  Purple or pale green capsule gall on both surfaces of the leaf, on S cordata [eriocephala]


externallink: https://www.biodiversitylibrary.org/page/4885236#page/304/mode/1up
description:
  Eriophyes semen

  Irregularly hemispherical, greenish yellow, pocket gall on either surface, on S nigra.

  Eriophyes sp.

  Small and very crowded, pocket galls on leaves of S nigra


externallink: https://www.biodiversitylibrary.org/page/4885236#page/305/mode/1up
description:
  Eriophyes aenigma

  Filamentous structures on leaf

  Eriophyes aenigma

  A mass of small, filamentous structures on leaf or stem, sometimes on distorted buds, on S nigra

  Eriophyes aenigma

  A mass of filamentous structures on the stem


externallink: https://www.biodiversitylibrary.org/page/4885236#page/305/mode/1up
description:
  Pontania desmodioides

  Smooth, flattish, fleshy, sessile, yellowish green, on both surfaces of the leaf, length 6 to 12 mm, on S humilis.


externallink: https://www.biodiversitylibrary.org/page/4885236#page/305/mode/1up
description:
  Pontania hyalina

  Ovate, fleshy, reddish, willow leaf galls in parallel rows on either side of the midrib, brownish red, beneath white, tinged with purple, length 7 to 10 mm, on S fragilis


externallink: https://www.biodiversitylibrary.org/page/4885236#page/306/mode/1up
description:
  Pontania pisum

  Subspherical, pealike, hollow, pale yellowish green gall on under side of leaf, usually on a side vein, diameter 5 to 7 mm. 


externallink: https://www.biodiversitylibrary.org/page/4885236#page/306/mode/1up
description:
  Pontania pomum

  Rounded or ovate, fleshy, yellowish green, usually rosy-cheeked gall, projected slightly on the upper surface, diamter 12 mm.


externallink: https://www.biodiversitylibrary.org/page/4885236#page/306/mode/1up
description:
  Pontania petiolaris

  Very similar gall [to Euura salicispomum], prominent on both surfaces of the leaf, on Salix petiolaris


externallink: https://www.biodiversitylibrary.org/page/4885236#page/307/mode/1up
description:
  Phytophaga caulicola

  Slender twigs slightly enlarged

  Rhabdophaga caulicola

  Slender twigs slightly enlarged


externallink: https://www.biodiversitylibrary.org/page/4885236#page/307/mode/1up
description:
  Euura nodus

  Gradual enlargement of the twig, usually extending partly around it and several near each other, polythalamous, length 1 to 3 cm.


externallink: https://www.biodiversitylibrary.org/page/4885236#page/307/mode/1up
description:
  Euura macgillivrayi

  Gradual twig enlargement, length 30 mm, diameter 7 to 10 mm, on S luteosericea [exigua]


externallink: https://www.biodiversitylibrary.org/page/4885236#page/308/mode/1up
description:
  Rhabdophaga triticoides

  Twig irregularly enlarged, gall 1 to 3 cm long, the stems between the buds dwarfed, giving a "wheat ear" appearance


externallink: https://www.biodiversitylibrary.org/page/4885236#page/309/mode/1up
description:
  Euura bebbianae

  Abrupt, elongate twig swelling, length 10 to 35 mm, height 8 to 11 mm, width 7 to 12 mm, on S rostrata [bebbiana]


externallink: https://www.biodiversitylibrary.org/page/4885236#page/309/mode/1up
description:
  Cryptorhynchus lapathi

  Irregular, branch and trunk swellings, mostly on branches or smaller stem s produced by transverse galleries just under the bark


description:
  An abrupt, globular-fusiform swelling along the midrib of Salix interior, showing on both sides of the leaf and causing it to curl either upward or downward. Observed in Iowa, Minnesota, and Ohio in [July](https://bugguide.net/node/view/542508) and September.


description:
  Long, thin, conical, hairless galls projecting straight up or slightly leaning from near the midrib of an undetermined Salix sp. [bebbiana chosen as a plausible placeholder]. The galls are much longer than those of similar Iteomyia spp, and are distinct in having largely symmetrical projections above and below the leaf. The projections sometimes diverge into fasciation-like fingers at the tip. Early galls and shaded galls are yellow-green while those exposed to the sun turn a strong [ripe-chili-pepper red by late July.](https://bugguide.net/node/view/67942/bgimage) Dense clusters are sometimes associated with curling of the leaf. Observed in Alaska in June and July. 


description:
  [Bowser et al sequence the genomes of R strobiloides specimens reared on Salix hookeriana, barclayi, commutata, sitchensis, richardsonii, and bebbiana in Alaska and on Salix nigra in Michigan. They find that these samples are monophyletic with respect to other Rabdophaga specimens they sequenced and conclude the Alaskan midges are Rabdophaga cf strobiloides and may be conspecific with R strobiloides. They note that previous studies have listed R strobiloides on Salix cordata, eriocephala, humilis, nigra, and scouleriana.]

  Morphologically, all galls of Alaskan Rabdophaga that we collected were more open than what is typical of R. strobiloides. In the key of Gagné (1989) they would have been identified as R. salicisbrassicoides, R. salicisrhodoides, or Rabdophaga saliciscoryloides, which form more open rosette galls. Most Alaskan rosette galls more closely resemble illustrations and photographs of European R. rosaria than any of these North American species. An exception is the unusual morphology of rosette galls on S. sitchensis, which often contain more than one midge larva and which often have new stems originating from leaf axils within the galls. 


description:
  [Bowser et al sequenced genomes of galls similar to Rabdophaga rosaria found on Salix pulchra and fuscescens and found they clustered with sequences from R rosaria on Salix purpurea in Poland. They "tentatively identify Alaskan members of this clade as Rabdophaga cf rosaria," but state that "Alaskan specimens of Rabdophaga cf. rosaria were different enough from the one Old World sequence of R. rosaria that they may represent separate species."]


description:
  [Sato et al report that Rabdophaga rosaria midges collected on Salix pulchra in Alaska are monophyletic with midges collected from similar galls in Eurasia. They note that the genetic distance between two clades of R rosaria are sufficient to suggest they have diverged as sister species, but the clade including the Alaskan midges is also found in Poland, Russia, Korea, China, and Japan.]


description:
  [Sato et al sequenced the genomes of Rabdophaga strobiloides from Salix sitchensis and barclayi in Alaska and Salix nigra in Michigan and found they were monophyletic.]


description:
  Small, densely white-hairy cone galls on lateral buds of Salix exigua, resembling [Rabdophaga strobiloides](https://www.gallformers.org/gall/1634) but with many fewer visible leaflets and more angled tips on those leaflets.  Observed in New Mexico in September.


description:
  Rabdophaga strobiloides is the most common and widely distributed of the willow leafy galls, and is easily distinguished from most of the other described species by its tightly appressed habit (salicisgnaphalioides and salicisstrobiliscus share this habit). The leaflets that make up the gall may gradually loosen over time, especially toward the tip, but never around the base, and in general they remain bound into a spherical or conical-oblong object. However, galls in Alaska with an open habit diagnostic of a range of other Rabdophaga species either in Europe or in the rest of North America have been sequenced and found to be monophyletic with R strobiloides specimens with the typical closed habit. 


description:
  While R salicisstrobiliscus remains a valid species according to the 2021 Gagne catalog, it is dubiously distinct from [R strobiloides](https://www.gallformers.org/gall/1634) both in gall, larval, and adult forms. The distinctions in gall morphology between the Alaskan R cf strobiloides (see ID notes on R strobiloides) and R strobiloides are much larger than those between R strobiloides and salicisstrobiliscus. Trying to distinguish the two galls is likely a waste of time. 


description:
  A slight, tapered swelling at the base of the petiole of Salix glauca, similar to [Euura cosensii](https://www.gallformers.org/gall/3542). Observed in Yukon in February. 


description:
  Salix candida added as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/105154373). 

  Salix bebbiana added as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/85376419). 

  Salix alaxensis added as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/28867035). 


description:
  Large globular galls formed on flowers of Spermacoce verticillata. The galls deform the flowers beyond recognition and may be mistaken for stem galls, attached at leaf nodes. The surface is hairless but rough and peeling. Observed in southern Florida in January. 


description:
  A tapered stem swelling, approximately 1.5x the diameter of the stem below it, on Aloysia wrightii. Observed in New Mexico in January. 


description:
  Lasioptera sp.
  Lily-stem-gall midge
  [Page 328]

  Hosts: Triteleia laxa, Brodiaea californica, Dichelostemma capitatum, congestum

  Galls can be smooth and symmetrically tapered or abrupt and somewhat knobby.

  Range: Napa county CA


description:
  Callirhytis flavens, new species

  Gall--Subglobular, found singly, in clusters, or several grown together on leaves projecting above and below and sometimes inhibiting the growth of the leaf. The color when mature is light green, sometimes tinged with red. Internally composed of a pithy substance. Diameter 2-5 mm.

  The type material was collected by Miss Georgie Bentley in May. Adults emerged in the breeding room during the summer. [Only a female is described.]

  Host: Quercus vaccinifolia, chrysolepis

  Range: Eldorado County, Santa Clara County CA, 

externallink:
  https://www.google.com/books/edition/California_Gall_making_Cynipidae/Jn5OAAAAMAAJ?hl=en&gbpv=1&pg=PA5&printsec=frontcover


description:
  A distinct swelling of the pedicel by which one or more acorns is attached to a stem on Quercus agrifolia. Observed in California in October. 


description:
  A cream-colored, slightly hairy open cup with a ring of spurs below the rim, near the leaf edge on Quercus chrysolepis. Observed in California in September.

  This is Joyce Gross' [Gall type #7](https://joycegross.com/galls/gall007.html), and her observation is apparently the only report of this gall. She suggests it may be Weld's Figure 178, which refers to a [very different gall on Quercus dumosa](https://www.gallformers.org/gall/2404). This may be a typo and meant to refer to either Figure [177](https://www.gallformers.org/gall/2403) or [176](https://www.gallformers.org/gall/2065), but neither of these galls match the open top or ring of spurs shown in her photos. 


description:
  A stem club similar to those induced by [Callirhytis clavula](https://www.gallformers.org/gall/847), on Quercus kelloggii. Observed in California in October.


externallink: https://babel.hathitrust.org/cgi/pt?id=coo.31924018313555&view=1up&seq=84
description:
  [Undescribed species tentatively matched to H crescentus based on the similarity of the photo to Lyon's drawing]

  Quercus chrysolepis
  Leaf galls, integral
  Small hollow sphere, dia 3.6 mm. Exit hole on under side of leaf. Fig 104.

  Fig 104. A small sphere projecting more on under side of leaf. Q. chrysolepis. Galls collected in summer and fall have been empty. 


externallink: https://babel.hathitrust.org/cgi/pt?id=coo.31924018354765&view=1up&seq=29
description:
  Quercus wilcoxii [chrysolepis]
  Leaf galls
  Integral
  Hard smooth parenchyma thickenings, single or in numbers, Fig 116.


description:
  Quercus lobata is added tentatively as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/95105786).


description:
  Galls are 5-9 mm. in diameter on S. jacobaea, and are nearly round to just irregular swellings on Ratibida as reported by Felt (1940). Usually only one gall is produced per plant. Reared E. angusta from Senecio sylvaticus and from the upper part of the root crown of S. jacobaea. Galls on Chinese aster and Senecio sylvaticus are reported as stem galls; the galls on the other host plants are upper root or crown galls.

  (Crown gall on Ambrosia psilostachya, Ambrosia sp. Ratibida columnaris, Ratibida sp., Senecio jacobaea; Stem gall on Callistephus chinensis, Senecio sylvaticus)


description:
  Steck reared this species from root crown and stem galls of Englemannia peristenia collected in Bastrop Co., Bastrop, 6.v.1977 and 4.v.1985 and from root crown galls of Wedelia texana in Travis Co., Austin, 14.iv and 4.v.1985.


description:
  This gall was found about 60 cm above ground on the woody stem of a large plant of Senecio sylvaticus L. The only record from S. jacobaea occured when 9 flies when reared from galls on 7 of 15 plants collected Oct. 8, 1969, near Fort Bragg. All the galls made by the larvae on S. jacobaea were on the upper portion of the root crowns and frequently on one side where the feeding usually killed a few leaves but did not seriously injure the plants. However, 1 gall was at the top center of a root crown, and on this plant, the larval feeding killed the growing tip above the gall and then the whole plant. Galls measured 5-9 mm diam.


externallink: https://babel.hathitrust.org/cgi/pt?id=coo.31924018354765&view=1up&seq=18
description:
  Quercus arizonica, oblongifolia, toumeyi, gambelii, subturbinella [turbinella]
  Bud galls
  Globular, smooth, bare. Fig. 20.


description:
  Weldia californica, new species

  Gall. Monothalamous bud or stem galls occurring singly or in groups of three to five; on current year's growth, if produced directly from stem, but, on two-year-old stem, if produced directly from terminal or axillary bud; galls produced from stems bear two, short, rounded projections at the point of attachment, one on each side of a groove occupied by the stem; galls produced from buds are circular at the point of attachment, often with bud scales clinging to gall base; subspherical in outline and flattened or even dimpled at apex (Q t californica [john-tuckeri]), surface mostly smooth with few irregularities; others circular, with low-level, rounded bumps over surface (Q douglasii). 

  Internal structure: Mature galls contain a subcentral, oval, larval capsule composed of an inner, nutritive cell layer (may be indistinct in mature galls) and an outer, hardened, protective, sclerenchymal layer; capsulre surrounded by thick zone of large, loosely packed, columnar cells, more compressed and hardened just beneath epidermis; epidermis composed of thin, hardened layer of small, compressed cuboidal cells, two-to-three cells deep, appear crystalline in cross-section. 

  Size: Average of 100 unparasitized galls: horizontal diameter, 12.2 mm; height, 11.6 mm.

  [Type locality: San Bernardino CA]

  Host records: Quercus douglasii, dumosa [berberidifolia? or possibly Q dumosa sensu strictu], Quercus turbinella californica [john-tuckeri] and various hybrids of these species and with other [white-group] oaks which are not hosts of W californica in the unhybridized condition. I have never seen galls of W californica on Q durata or lobata and only infrequently on Q dumosa where it occurs in the vicinity of either Q douglasii or Q t californica. 

  Range: Known to occur only in California from San Diego Co north to Lake Co and probably around the northern rim of the San Joaquin Valley as well, wherever Q douglasii occurs.

  Remarks: I at first thought this species to be Disholcaspis canescens while conducting biological studies on a large population at Cajon Pass. Later, I became aware that two distinct species, based on adults, were consistently placed together under D canescens in museum collections. This seemed peculiar since, with the exception of similar abdominal setation, the adults of both species are distinct. Bassett's type adult of D canescens matched the original description, but cotype galls did not and proved to be galls of W californica. Apparently, galls of D canescens, W corallina, and W californica were sent to Bassett in the same shipment from Napa CA and subsequently were mixed. The failure of later works, myself included, to correctly separate these species, is witness to the often misleading reliance placed on gall characteristics which may be only superficial.

  Gall growth. Young galls of W californica first appear on Quercus turbinella californica [john-tuckeri] in mid-June as elongate evaginations of new stems or from terminal and axillary buds in which incipient stems were inhibited by early eclosion and larval feeding. These new galls are pale green and bear a dense coat of short, colorless pubescence which generally weathers away as they mature. Initial gall growth is rapid and by 1 August, they are approximately 7-8 mm in diameter, reddish green, and contain a thick-walled larval capsule composed entirely of moist, nutritive tissue closely surrounding the larva. By 15 September, galls are full-sized and average ca. 12 mm in diameter. The outer surface turns a deep red and the surface pubescence begins to weather away. The larval capsule, ca 3.5 mm in greatest diameter, is full-sized by this time and considerably larger than the third instar larva within. Galls are usually mature, medium brown and glabrous by 1 October. Internal tissue is dry and rust-colored and the mature, C-shaped larva completely fills the larval capsule. 

  Four distinct zones of tissue, ie, epidermis, collenchyma, parenchyma and the sclerenchyma of the larval capsule, may be distinguished in sections through the mature galls. The inner nutritive layer of the larval capsule, the larval food source, is usually indistinguishable in mature galls.

  Rearing adults. During October, 1974, mature galls were collected from oak branches at Site No 1 [26 miles northwest of San Bernardino] and maintained outdoors in rearing containers at Riverside, CA. Adult emergence in these containers began on 16 November and continued until 15 December. Emergences were most frequent in the early-morning hours and rare after midday. No emergence occurred on windy days of below-normal relative humidity. The largest number of emergences followed rain and/or periods of heavy fog.

  Galls dissected, prior to normal emergence, exposed a variable degree of emergence-tunnel completion. The adult female chews an emergence tunnel leading from the larval capsule to the epidermis, through the side of the gall, midway between apex and the point of attachment to the stem. Many galls contained completed emergence tunnels except for a thin epidermal layer that separated the insect from the outside environment. During periods of subnormal relative humidity, females were found resting, sometimes for several days, just beneath this epidermal "window." Once she began chewing, the female could exit the gall within an hour. Many galls that bore no exit hole after the normal emergence period ended contained dead females in partially completed emergence tunnels. 

  [Burnett gives a description of the results of oviposition experiments, detailing when and where the female oviposits]

  Early egg eclosion occurs before new stems begin to grow beyond the bud scales and results in the complete inhibition of normal plant tissue development in the bud. Consequently, galls appear to arise directly from within the bud. On 27 May, such galls were 1-2 mm in diameter, pale green, and spherical with an apical red nipple. Buds become laterally distorted as galls enlarge to occupy the entire bud base. On 14 June, small galls were observed growing from buds on year-old wood, not growing directly from within a bud. Late eclosion occurring after new stem growth has begun results in true stem galls, as the eggs or larvae are carried away from the area of original egg deposition. 

  [From key to galls, page 176 of the pdf] 

  1. Subglobular stem and leaf petiole galls without apical projection or strong surface tubercles; surface may be smooth or bumpy

  2. Stem galls on white oaks of the Pacific Slope from northern Baja California to points north; larval capsule spherical or oval, positioned centrally or basally in parenchymal tissue; under 14 mm in diameter.

  3. Outline symmetrical, larger apically; larval capsule oval, basally positioned in parenchymal tissue; surface smooth or slightly bumpy; occurs in California on Q douglasii, Q dumosa, and Q turbinella californica [john-tuckeri]


description:
  This gall and wasp were originally described in Burnett 1977's PhD thesis as Weldia californica, on the type host Quercus turbinella californica and hybrids with Quercus dumosa at a type locality near San Bernardino. Under modern nomenclature, it's likely his type host is what is now called Quercus john-tuckeri, and his Quercus dumosa may be Quercus berberidifolia (though Quercus dumosa sensu strictu may be possible at his type locality). Burnett also reports the gall on Q douglasii, in places from San Diego to Lake County CA (north of San Francisco). 

  Melika et al redescribe the gall from new specimens collected only in Baja California, on a host they list only as Quercus turbinella. 

  Quercus turbinella and engelmanni are relatively distantly related to the other California white oaks, and no other members of the genus Burnettweldia are known from oaks not in subsection Dumosae. 

  According to Burnett, one key trait distinguishing his W californica from plumbella was an oval larval cell placed basally toward the attachment point. However, Melika et al's cross section photo shows a spherical and central larval cell for their B californicordazi. 


description:
  Weldia plumbella, new combination

  Disholcaspis plumbella
  Adleria plumbella

  Gall: Monothalamous bud or stem galls occurring singly or in clusters on young stems; stem galls bear an elongated groove at the point of attachment (an indentation made by the stem); bud galls bear a circular indentation at point of attachment (which corresponds to the shape of the bud base); most galls spherical, some with an apical projection 1 to 3 mm long, sharply pointed, others without such a projection; surface usually smooth, bare. 

  Internal structure: Larval capsule spherical, centrally positioned in gall, composed of two layers, inner nutritive and outer protective layer; nutritive layer indistinct or absent in mature galls, outer layer thin; capsule surrounded by parenchymal tissue composed of elongate, woody columnar cells radiating away from point of attachment; flattened collenchymal zone positioned just below epidermis composed of compressed cuboidal cells; epidermins composed of small crystalline cells compressed into a thin lyaer 1 or 2 cells deep, forms hardened surface. Color: Growing galls pale green with whitish spots when in constant shade, shades of brilliant red or wine with yellow spots when constantly exposed to direct sunlight; mature galls light brown with pale yellow spots which are occassionally embossed, distributed uniformly over gall surface. Size: Average of 100 unparasitized galls: horizontal diameter, 10.6 mm, length of apical projection, 1.9 mm (galls without apical projections not included in the latter measurement). 

  Galls of W plumbella vary considerably in size and in some populations 80% of galls lack the apical projection. Galls on Q turbinella californica [john-tuckeri] at desert margins are typically small (9 mm or less in diameter) with only an apical nipple or short, thin projection. Galls on Q dumosa, from Monterey Co northward, bear a long, stout apical projection to 3 mm or more in length. 

  Hosts: Quercus dumosa, durata, and turbinella californica [john-tuckeri] 

  Range: CA and northern Baja California

  Gall Growth. New galls appeared on Q dumosa at Site No 2 [near San Bernardino] on 2 May 1974, and on Q t californica [john-tuckeri] at Site No. 1 [also near San Bernardino] ca mid-June. Small galls growing from within bud scales and later on new stems were pale green with reddish patches when exposed to the sun. At this time, many galls possessed a blunt apical projection. Galls which failed to exhibit this character were round and smooth apically at maturity. By 1 August, most galls at Site No 2 were approximately 5 mm in diameter and distinctly pointed apically with an orange-red background color and bright yellow spots. Galls growing on lower branches and shaded from direct sunlight were various shades of green with white or yellow spots. On 1 October, galls were full-sized (ca 10.5 mm in diameter), round, moist internally, and still vividly colored. By 10 November, they had weathered to a light tan and the yellow spots were either absent or subdued.

  The internal structure of the mature galls is similar to that described for galls of [W californica](https://www.gallformers.org/gall/2523), however, the cells of the parenchyma are smaller and less elongate in W plumbella and the larval capsule is round and centered in the gall. In galls of W californica, the larval capsule is oval and subcentral. 

  Old galls rarely are numerous on branches, as their attachment to stems is fragile and they are easily knocked to the ground by wind and rain. Frequently after a storm, 60-80% of the galls in an area (even those from which adults have not yet emerged) may be found lying on the ground, where they fall prey to birds and rodents which crack them open, apparently to eat the contained insects.

  Galls arise from either terminal or axillary buds on the previous year's branch or from a new branch of the current year's growth. As with galls of W californica, W plumbella stem galls result when eggs in buds hatch after new stems have begun to grow. This causes the newly emerged first instar larva and its surrounding gall tissue to be carried with the stem as it grows. The mature stem gall may ultimatley rest several centimeters beyond the original site of oviposition. Bud galls result when eclosion occurs prior to incipient stem growth. Mature bud galls may be recognized by the presence of scales clinging to the gall base. 

  Rearing Adults. Mature galls were collected from Q dumosa [berberidifolia?] near Site No 2 in September and October, 1974, and kept outdoors as rearing stock for oviposition experiments. Normal emergence of parthenogenetic females began on 7 October and continued until 21 November. 

  [Burnett goes on to describe findings of dissections and oviposition experiments. 

  [From key to galls, page 176 of the pdf] 

  1. Spherical or cone-shaped stem galls, usually with an apical projection or strong surface tubercles

  4. Surface smooth; pointed apically

  5. Surface of mature galls brown or reddish with yellow spots (uniform light brown when weathered), smooth, usually with pointed apical projection; larval capsule central, spherical, thin-walled; on Q dumosa, durata, Q turbinella californica [john-tuckeri] and hybrids.


description:
  Weldia sulcata, new combination

  Cynips sulcatus
  Cynips sulcata
  Disholcaspis sulcata

  Gall: Monothalamous leaf-petiole galls occurring singly on leaves of [white-group] oaks; subglobular in outline, smaller galls spherical; surface of mature galls smooth; parenchymal tissue granular, loosely packed; larval capsule spherical, may be central or eccentric within gall, wall indistinct; growing galls light green when shaded, yellowish-red in direct sunlight; mature galls faded green to light brown on surface, light brown internally; not deciduous, but remain attached to leaf petiole and drop with leaves in fall. Horizontal diameter of 50 unparasitized galls 7.8 mm.

  Although galls of W sulcata are known to occur only on the leaf petiole where it is attached to the stem, they are remarkably similar to those of W californica, in shape, surface and internal texture and color. The major differences are in the smaller size and often eccentric position of the larval capsule in galls of W sulcata. 

  Host records: Quercus arizonica, oblongifolia, pungens, rugosa, toumeyi, turbinella turbinella, and undulata

  Range: AZ and western NM. It probably occurs in northern Mexico as well, wherever its host ranges.

  The galls I have examined in collections and in the field have all been monothalamous, containing a single larval capsule. Occasionally, two galls may coalesce and appear to be bithalamous, but this is rare.

  [From key to galls, page 176 of the pdf] 

  1. Subglobular stem and leaf petiole galls without apical projection or strong surface tubercles; surface may be smooth or bumpy

  2. Leaf petiole galls on white oaks of Arizona and New Mexico; surface light brown, smooth; larval capsule spherical, irregularly positioned in parenchymal tissue, thin-walled; under 10 mm in diameter.


description:
  Weldia washingtonensis, new combination

  Cynips washingtonensis
  Disholcaspis washingtonensis

  Gall: Monothalamous stem galls occurring singly on young stems; some mature galls spherical others oblate; surface of mature galls smooth, pebbled or somewhat wrinkled due to shrivelling; growing galls green or reddish with a long whitish pile which weathers away at maturity, mature galls medium brown, turning black with age; epidermis thin, brittle; parenchyma light brown, with large, parallel, columnar cells radiating away from larval capsule; larval capsule positioned in center of gall, oval, large, thick-walled, nutritive and protective layers usually distinct; weakly attached to stem by a small, circular projection allowing some galls to drop to the ground in severe weather. Horizontal diameter of 50 mature galls, 9.7 mm.

  Galls of W washingtonensis, in their various forms, are occasionally difficult to separate from those of W californica and W plumbella (when the apical projection is absent) in outward appearance. However, in galls of W washingtonensis, the larval capsule is, without exception, centrally located (subcentral in W californica), large relative to gall size and oval (smaller and spherical in W plumbella). Growing and newly mature galls are covered with a long, whitish pile which turns rust-colored with age, a characteristic unique in the genus Weldia.

  Galls are highly variable in size, shape, and epidermal sculpture which appears, at least in part, to be host related. For example, galls growing on Q garryana, near the summit of Liebre Mountain in northern Los Angeles Co., are small (5-8 mm in diameter), spherical and studded over the surface with numerous, blunt-tipped projections. At the same location, only 20-30 geet away, galls on Q dumosa are subspherical with an entirely smooth surface and average 3 mm larger in horizontal diameter. Adults from galls on the different hosts are not separable. If two species are represented by the different gall forms, I am unable to distinguish them using established taxonomic characters based on the few specimens at hand. All gall forms of W washingtonensis are similar internally and during the growing stage. 

  Hosts: Quercus douglasii, dumosa, durata, garryana, and lobata. Quercus lobata records are questionable. I have not found galls of W washingtonensis to occur on any of the hundreds of "valley oak" inspected over the years since I first became interested in cynipid galls. But, on several occasions I have observed these galls on Q lobata X douglasii, many trees of which could easily have been casually taken for Q lobata.

  Range: Weldia washingtonensis is the most widely distributed species in the genus. Known to occur from southern San Diego Co CA, more or less continuously, to Benton Co in northern WA, west of the Sierra Nevada and Cascade Mountains of the Pacific Slope. 

  [From key to galls, page 176 of the pdf] 

  1. Subglobular stem and leaf petiole galls without apical projection or strong surface tubercles; surface may be smooth or bumpy

  2. Stem galls on white oaks of the Pacific Slope from northern Baja California to points north; larval capsule spherical or oval, positioned centrally or basally in parenchymal tissue; under 14 mm in diameter.

  3. Compressed oval in outline; larval capsule large relative to gall size, oval, centrally positioned in parenchymal tissue; surface smooth (wrinkled or pebbled on Q garryana), with long whitish pile while growing; common on most white oaks from Baja California to Canada


description:
  Weldia corallina, new combination

  Holcaspis corallinus
  Holcaspis corallina
  Disholcaspis coralline
  Cynips corallina

  Gall: Monothalamous stem galls occurring singly or in clusters of 2-4 on Q douglasii, numerous on some trees; basically globular in outline, some spherical, others dome-shaped at apex and truncate at base above point of attachment; surface of mature galls usually studded with blunt peg-like projections; in some galls the surface projections are reduced to regular rounded bumps or tubercles; parenchymal zone thick, hard, crystalline, reddish-pink; larval capsule thick-walled, oval, usually located in gall base just above point of attachment; new galls yellow-green, growing directly from young stems, coated with velvety, whitish, stellate pile which weathers off at maturity; full-sized galls red or wine colored, old galls black; not deciduous. Horizontal diameter of 100 unparasitized galls, 10.8 mm.

  Two basic types of epidermal sculpture are observed in galls, one form with short, peglike projections uniformly distributed over the surfaace of rather spherical galls, the other type with large, rounded pumps or tubercles externally, more prominent at the base of dome-shaped or mushroom-shaped galls. These differences appear to be geographically related with the former occuring from Fresno Co in central CA, northward around the San Joaquin Valley rim and in areas of 1000-2000 feet or more in elevation. Galls with rounded bumps or tubercles occur south of central Fresno Co on the western slopes of the Sierra Nevada Mountains as far south as Tehachapi at elevations between 1500 and 3500 feet. As with galls of other species in the group, differences in epidermal sculpture may result from differences in moisture available to growing galls, depending on the amount of annual rainfall, host species, soil type, drainage, and other factors. 

  Host: Quercus douglasii, durata, and garryana(?). It is possible that W corallina is hosted only by Q douglasii and its hybrid forms. 

  Range: around the margin of the San Joaquin Valley

  [From key to galls, page 176 of the pdf] 

  1. Spherical or cone-shaped stem galls, usually with an apical projection or strong surface tubercles

  4. Surface of mature galls deep red, studded with, more or less, uniform, blunt tubercles; parenchyma hard, crystalline; larval capsule basal; on Q douglasii and its hybrids.


description:
  Weldia conalis, new combination

  Disholcaspis conalis

  Gall: Monothalamous stem galls occurring singly or rarely in clusters of 2-5, never found on host tree in large numbers; conical in outline with entire gall drawn out to gradually tapering at apex, straight in some, bent over or lopsided in others; base above point of attachment abruptly flared and symmetrically spherical in some, irregluar and clasping stem in others; internally thin-walled, oval, larval capsule centrally positioned in the gall base at its broadest point and situated perpendicular to the galls vertical axis; parenchymal tissue soft, but dense (not woody); epidermal layer thin; surface basically smooth, slightly folded in some; color of growing galls pale green with short, white pile which turns reddish and weathers off at maturity; mature galls light brown, old galls dark brown to black; not deciduous. Average size of 50 unparasitized galls; horizontal diameter, 8.5 mm; height, 12.6 mm.

  Hosts: Quercus garryana. No other hosts have been recorded, nor have I found galls on hybrids inspected near the type locality.

  Range: Known only from a few locations of the western slopes of the Sierra Nevada Mountains in central CA. It is apparently not correspondingly distributed with its host Q garryana which ranges from the Liebre Mountains in northern Los Angeles Co to the Canadian border and beyond.

  In mid July, 1976, new pale-green galls under 3 mm in diameter were observed bursting through the green bark of young Q garryana stems near Tollhouse CA. Other galls at the locality and at Sequoia Park were nearly full grown at this time, but still green in color and bearing a recumbent, whitish pile which was beginning to turn rusty red on larger galls. Fresh galls were growing directly from stems and none observed were associated with either terminal or axillary buds at that time. Large galls, those 8-10 mm high and 6-8 mm in diameter at the base, contained 3rd and 4th instar larvae housed in a moist, thick-walled larval capsule which later becomes so thin as to be barely noticeable in the dry mature galls. 

  [From key to galls, page 176 of the pdf] 

  1. Spherical or cone-shaped stem galls, usually with an apical projection or strong surface tubercles

  4. Surface smooth; pointed apically

  5. Entire gall drawn out into conical shape, broadened or clasping at base; green when young, light brown when mature; surface smooth or slightly longitudinally folded; larval capsule basal, oval; host specific to Q garryana in central California


description:
  Melika et al list Quercus berberidifolia as one of two hosts of this wasp, citing Burks in the Krombein 1979 catalog. However, [the Krombein catalog listing](https://www.biodiversitylibrary.org/item/24831#page/1111/mode/1up) for this species only lists Quercus garryana as a host, following every other source about this gall. They list no types examined from Q berberidifolia. This may be a mistake. It is notable that no other cynipid wasps are listed on Q berberidifolia in the 1979 Krombein catalog; this name was not in use at the time. 


description:
  Dryocosmus dubiosus agamic galls are very rarely found on the upper side of the leaf but it has been observed, [eg](https://www.inaturalist.org/observations/104486636). 


externallink: https://www.biodiversitylibrary.org/item/32802#page/24/mode/1up
description:
  Andricus furnessulus, new species

  Gall (pl. 2, fig. 10). — A woolly mass partly or entirely encircling small twigs, measuring up to 30 by 25 mm., pure white or rosy when young, consisting of a large number of separate biconical cells attached at a common point, each covered with long hairs. These measure about 7 by 5 mm., shorter and broader than in furnessae. 

  Host. — Quercus oblongifolia. 

  Habitat. — The type is selected from a series from a gall sent from Nogales, Ariz., by Mrs. N. W. Capron on February 4, 1935. Paratypes also are from a gall sent by Ed Jacot from Bear Canyon in the Huachuca Mountains, Ariz., March 30, 1919, the adults emerging May 10-28. The writer collected galls at Nogales and Patagonia, Ariz., and in the Santa Rita Mountains.


description:
  Salvia leucophylla added tentatively as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/105592091). Strictly speaking, Gagne's 2021 catalog lists only S. apiana as a host, but Russo adds S. mellifera.


description:
  Quercus agrifolia added tentatively as a host based on unconfirmed iNaturalist observations (see link below). 


description:
  Quercus grisea added tentatively as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/101207176).

  Quercus mohriana added as a host based on [this observation](https://www.inaturalist.org/observations/103440540)  in western Texas (also a new range record). The wasp was [confirmed to be D gregori by Victor Cuesta-Porta](https://www.inaturalist.org/observations/103440540#identification-bcbd8580-7209-4496-8908-e112437b84cf), but the species of the tree is not established with certainty; Quercus havardii is also possible, or a hybrid of mohriana and havardii.


externallink: https://www.biodiversitylibrary.org/item/32322#page/85/mode/1up
description:
  Andricus (Callirhytis) pilula, n. sp.

  Small, round, thin-shelled galls on the blade of the leaves of Q. undulata, collected in southern Utah by Mr. Siler. They are usually situated near the margin of the leaves and always on one of the principal leaf veins, and project equally above and below the surface. The average size is only .15 of an inch in diameter. The galls resemble those of [Neuroterus utricula Bass](https://www.gallformers.org/gall/867), more nearly than any other species known to me. I found twenty-five or thirty specimens in a box of A. Sileri, and was so fortunate as to find two of them that, though perforated, still contained the gall-flies. These were both females, quite perfect, and the description that follows will, no doubt, well agree with more recent specimens.


externallink: https://www.biodiversitylibrary.org/page/15672479#page/376/mode/1up
description:
  Andricus pilula

  This species was described from two females cut from galls from southern Utah. The types have the claws toothed, not simple as described. Similar galls were collected by Dr. A. W. Grundmann on Quercus gambelii in the mountains near Salt Lake City, Utah, and both females (agreeing with the types) and males were reared June 1-5, 1949. A description of the male is given below.


externallink: https://www.biodiversitylibrary.org/page/15672479#page/377/mode/1up
description:
  Andricus pilularis, new species

  Host: Quercus turbinella

  Gall. — Similar to galls of [Andricus utriculus Ashmead](https://www.gallformers.org/gall/867) and [A. pilula Bassett.](https://www.gallformers.org/gall/2547) Globular, about 4 mm. in diameter, projecting more on upper side of leaf. 

  Habitat. — The types are from galls collected at Wolf Creek, near Prescott, Ariz., by Mrs. N. W. Capron, in June and July 1935. Living adults were cut out of the galls on July 20 and August 15. Others were sent August 1, 1947, and adults cut out August 7. One paratype is from a gall on Quercus oblongifolia, from Nogales. Galls have been noted on Q. toumeyi., Q. submollis [gambelii], Q. gambelii, and Q. diversicolor [rugosa].


externallink: https://www.biodiversitylibrary.org/page/8635502#page/108/mode/1up
description:
  Andricus pilula

  Small, round, thin-shelled galls on leaf blades, usually near the margin and always on the upper leaf veins, projecting on both surfaces, diameter 3.7 mm, on Quercus undulata.


description:
  Numerous small blister galls scattered around a leaf of Quercus gambelii, clustered principally but not exclusively on the midrib and lateral veins. These galls conform to Kinsey's [species-level description of Neuroterus niger,](https://www.biodiversitylibrary.org/page/53512324#page/297/mode/1up) but none of his varieties have been reported from this host. Observed in Utah in October. 


externallink: https://www.biodiversitylibrary.org/item/88723#page/199/mode/1up
description:
  Holcaspis arizonica, n. sp.

  Gall globular, 9 mm. diam., pale ochreous, not shiny, attached to the base of the petiole of a leaf of Quercus arizonica, Sargent. There is a projecting point next to the place of insertion. Within, the gall is brown, fibrous, moderately dense, at least dithalamous. 

  Range: Prescott, AZ


description:
  A globular stem swelling on one side of a twig of Quercus emoryi, causing the stem beyond to bend nearly 180 degrees. Observed in Arizona in March. Cf a [similar gall on Quercus wislizeni and agrifolia](https://www.gallformers.org/gall/2139).


externallink: https://www.biodiversitylibrary.org/page/7562993#page/281/mode/1up
description:
  Callirhytis ellipsoida, new species

   Host. — Quercus bicolor Willdenow. 

  Gall. — Ellipsoid, 4.5 by 5.5 mm., single or in small clusters on the small roots just below surface of ground under the tree. Surface smooth, brown. Monothalamous with a firm wall less than one-half millimeter thick when mature, exit hole at end 2 mm. in diameter. Immature galls lighter in color, fleshy, translucent white inside. 

  Habitat. — Type locality, Wilmette, Illinois. Collected also at Evanston and Winnetka, Illinois. 

  Biology. — The galls probably take two years to develop, the larvae transforming to adults the second autumn but not emerging from the galls until the following spring between April 15 and May 7. They are all females. They oviposit at once in the swelling buds of the same tree, but the alternating sexual generation is unknown. 


externallink: https://www.biodiversitylibrary.org/page/7562993#page/282/mode/1up
description:
  Callirhytis elliptica, new species

  This species can be separated from [Callirhytis ellipsoida Weld](https://www.gallformers.org/gall/924) only by color markings which, however, seem to be constant. The galls also are similar but on a different oak [Quercus bicolor]. 

  Host. — Quercus alba Linnaeus. 

  Gall. — An abrupt ellipsoidal swelling on small rootlets found an inch or two under the humus on forest floor underneath large trees. Brown, smooth, thin-walled when mature, monothalamous, and similar to galls of [Callirhytis ellipsoida Weld](https://www.gallformers.org/gall/924) on Quercus bicolor but the fly is different. 

  Type locality. — The type fly was cut out alive from a gall found at Highland Park, Illinois, October 22, 1916, on root of an undetermined oak. On May 11, 1919, five similar flies were collected at Glencoe, Illinois, ovipositing on buds of Quercus alba. On May 23, 1919, found similar galls on roots of white oak at Ravinia, Illinois. Some showed exit holes from which flies had recently emerged; others were full grown but contained a thick translucent nutritive layer and a barely visible larval cavity; others had a large cavity and a third of the nutritive layer left and a nearly full-grown larva which would probably transform in the fall and emerge next spring in early May. In the United States National Museum are three similar flies collected by J. G. Barlow at Cadet, Missouri, April 27 and May 5, 1883, ovipositing in buds of white oak. Also two from Nyack, New York, collected by J. L. Zabriskie, April 21, 1885, on buds of Quercus alba. 

  These galls were also collected at Marianna, Florida, October 10, 1919, on the roots of Quercus alba growing in deep woods. A dead adult was cut out on December 6, and mounted in balsam. This agrees with the type material and proves the type gall to have been on white oak. Galls collected in Washington, District of Columbia, on alba contained living flies on October 31, 1920. 


description:
  The sexual generation of this gall is apparently consistent with an undescribed species Weld listed from Quercus toumeyi and turbinella as well as oblongifolia. Those species are added tentatively as hosts of this agamic gall as well based on the assumption that the undescribed species was in fact Neuroterus aliceae. 


description:
  Conobius (spicatus) strues, new species
  Agamic form

  GALL.—As described for the genus; distinguished as follows: color dark reddish brown, probably weathering darker; individal galls up to 9 mm in length and 6.5 mm in diameter; the whole cluster up to 23 mm in diameter.

  [Description for the genus, shared with [Conobius spicatus](https://www.gallformers.org/gall/2123): Woody, seed-like cells densely clustered on stems, the clusters resembling small nubbins of dent corn. Each cell monothalamous, roughly conical, sharply pointed at place of attachment, expanding into a broadened, distinctly flattened top, the top centrally tipped with a small scar, the individual galls mis-shapened, often flattened on the sides because of the pressure within the cluster of galls: each cell covered with a thin, hard-papery epidermis which usually shrivels or becomes fluted, and sometimes flaker off in dried galls.]

  The galls are practically identical to those of spicatus.

  HOSTS.—Quercus undata, an evergreen white oak with ovate leaves which are soft pubescent beneath

  RANGE.— Chihuahua. Santa Isabel, 6 E 6000'

  LIFE HISTORY.—Adults: March 1


description:
  Conobius (spicatus) spicatus (Bassett) 
  Agamic form

  Loxaulus spicatus
  Loxaulus spicata

  GALL.—As described for the genus, distinguished as follows : Color dark reddish brown, weathering dark to black, the old epidermis becoming quite ashy gray ; individual galls up to 9.0 mm. in length and 6.5 mm. in diameter ; the whole cluster up to 28. mm. in diameter. 

  [Description for the genus, shared with [Conobius strues](https://www.gallformers.org/gall/2122): Woody, seed-like cells densely clustered on stems, the clusters resembling small nubbins of dent corn. Each cell monothalamous, roughly conical, sharply pointed at place of attachment, expanding into a broadened, distinctly flattened top, the top centrally tipped with a small scar, the individual galls mis-shapened, often flattened on the sides because of the pressure within the cluster of galls: each cell covered with a thin, hard-papery epidermis which usually shrivels or becomes fluted, and sometimes flaker off in dried galls.]

  HOST. — Quercus grisea (Kinsey coll.). Q. arizonica. Q. oblongifolia. Q. Toumeyi (ace. Weld, 1926 ; possibly more than one species of cynipid involved). 

  RANGE.—New Mexico: Hillsboro. (Kinsey coll.). Arizona: Whetstone (galls, Q arizonica). Sabino Trail in Santa Catalina Mountains (galls, Q. oblongifolia, Kinsey coll. Also ace. Weld, 1926). Oracle Q. arizonica, Kinsey coll. Also ace. Weld, 1926). Huachuca Mountains, Mule Mountains, Santa Rita Mountains, Patagonia Mountains (ace. Weld, 1926). 

  Probably restricted to southernmost Arizona and immediately adjacent portions of New Mexico

  This species appears to be the only American representative of the complex, though we have galls of other species of the group from a wide area in western Mexico, as far south as Jalisco. The galls of spicatus and strues are hardly distinguishable. Spicatus was originally described as a species of Loxaulus. True Loxaulus, according to my studies, includes the genotypes of Compsodryoxenus. The genus (Mayr, 1881, Gen. gallenbew. Cynip. :9, 12, 33) was monobasic, with Bassett's species mammula as type; but spicatus is not at all closely related to true Loxaulus. Weld (1926, Proc. U. S. Nat. Mus. 68 (10) :45) recognized this error in assigning spicatus to Loxaulus, but made no re-assignment of the species. 


description:
  Cynips (arida) conspecta, new species
  Agamic form

  GALL.—Similar to but readily distinguished from other galls of the complex. Mature gall almost strictly spherical, with a flat or slightly concave base; perfectly smooth, light led brown in color, with a white scurf which persists on at least part of the gall; up to 6.5 mm., averaging near 5.0 mm. in diameter.

  HOST. — Quercus Pringlei, one of the several scrub oaks of the region; replaced on other scrub oaks in the same area by C. rubella. 

  RANGE.—Tamaulipas : Miquihuana, 7 SE, 6000' (types). Known only from this one locality in the southwestern corner of Tamaulipas. 

  In our previous revision of the Cynips arida complex (Kinsey 1936, Ind. Univ. Sci. Ser. 4:217-237), the only species reported from the Eastern Mexican Sierra was Cynips saxifera, from a locality west of Ciudad Victoria, in the southwestern corner of Tamaulipas. From a few miles west of that same locality, from Miquihuana, which is still in Tamaulipas but immediately east of the main divides of the Sierra, we now have two more species to describe. 

  In this locality southeast of Miquihuana, there are several species of scrub or dwarf oaks, from three of which we have now bred insects of the present complex. Although these dwarf oaks are so closely related that it is often difficult to distinguish them in the field, we find that two perfectly distinct and not closely related insects are isolated on different oaks. The present species, C. conspecta, occurs on Q. Pringlei. As yet we do not have it from any other oak. It is C. rubella (described in the present paper) which occurs on the scrub oak, Q. intricata, and on the low dwarf, Q. cordifolia. The two cynipids are as different as the two most extreme forms in the arida complex. To note only a few of the differences: The galls of conspecta are nearly spherical, almost entirely smooth, and a bit smaller in average diameter; those of rubella are more hemispherical, distinctly shrivelled, and slightly larger in diameter. The insects of conspecta are almost uniformly brownish rufous, without any marks or blotches in the cubital cell, and with almost no infuscations at the base of the radial cell; the insects of rubella are red rufous with the lateral lines (and sometimes the anterior parallel lines) distinctly brown, and the splotches in the cubital cell and the infuscation at the base of the radial cell are distinct and of some size. Conspecta is most closely related to the contacta-eluta-eminida group of species from more southern Mexico; 266 Proceedings of Indiana Academy of Science rubella has its closest relatives in saxifera, from a more eastern part of the same Eastern Sierra, and in saxulum, from the Western Mexican Sierra. It is an interesting case of two branches of the one complex invading the one locality where they are, however, still separated by their restriction to different oak hosts. 

  From contacta, its geographically and evolutionary nearest relative, conspecta is to be distinguished by . . . its larger and more spherical gall. In contacta the gall is distinctly dome-shaped. 


description:
  Cynips (arida) rubella, new species
  Agamic form

  GALL.—Similar to other galls of the complex. Mature galls more or less hemispherical, with a broadly flattened base, shrivelling considerably so gall is usually irregular in shape ; light red or purple brown in color, with some white scurf ; up to 7.0 mm., averaging near 5.5 mm. in diameter. 

  HOSTS. — Quercus intricata, (types) ; Q. cordifolia [striulata]. The first is a shoulder-high scrub white oak, the second, the lowest dwarf oak of the region. Replaced on Q. Pringlei in the same area by C. conspecta. 

  RANGE.—Tamaulipas: Miquihuana, 7 SE, 6000'(Q. intricata, types. Also on Q. cordifolia [striulata].) Not yet known beyond this one locality in the southwestern corner of Tamaulipas, in a central portion of the Eastern Mexican Sierra. 

  This is one of the two species representing the arida complex near Miquihuana, in the southwestern corner of Tamaulipas. See the discussion under the other species, [C. conspecta](https://www.gallformers.org/gall/3757), in the present paper. As noted in that discussion, rubella is found on Q. intricata and Q. cordifolia, while C. conspecta is found on Q. Pringlei in the same area. The two cynipid species are not closely related. Rubella is most closely related to the species saxifera and saxulum. Saxifera also occurs in the Eastern Sierra of Tamaulipas, just east of the locality from which we have rubella. Saxulum is a widespread species in the Western Sierra of Mexico, from southern Chihuahua through Durango. 


description:
  Cynips (mellea) sagata, new species
  Agamic form

  GALL.—As described for the complex. Finally naked, or retaining part of the microscopic, stellate pubescence ; flesh-colored to light brown, with considerable solid matter; rounded or flat basally, occurring singly on leaves. 

  [Gall description for the complex: A small, globular, thick-walled leaf gall with the larval cell filling most of the interior. Monothalamous ; strictly spherical when fresh and sometimes when dried after maturity, often shrinking irregularly when dried; the gall sometimes drawn out at the point of attachment; the surface of the gall roughly, irregularly shagreened, densely covered with long, white or brown hairs when young (at least in some varieties), the hairs deciduous, leaving a stellate pubescence on older galls; the galls of all varieties finally naked (altho still appearing puberulent because of the shagreened surface; the naked galls whitish, flesh pink or pinkish brown in color; up to 7.0 mm., dried galls averaging about 4.0 mm. in diameter. The thin outer shell re-enforced with a more or less thin, solid mass of crystalline structure; the larval cell highly variable in size, often occupying most of the gall, the wall of the cell hardly differentiated from the solid, crystalline material. Attached to the veins, singly or in small clusters, on the upper or (less often) the under surfaces of leaves of white oaks of all groups.]

  HOSTS. — Quercus oblongifolia (types) ; and a tree form of Q. breviloba. In this area, these are the two most abundant tree-forms of white oaks. 

  RANGE.—Coahuila: Muzquiz, 7 SW, 3600' (Q. oblongifolia, types.) Muzquiz, 5 SW, 3000' (a tree form of Q. breviloba). Probably restricted to the most northern end of the Eastern Sierra of Mexico. 

  Previously we have described 11 species of this C. mellea complex (see Kinsey 1930, Ind. Univ. Studies 84-86:314-338; and Kinsey 1936, Ind. Univ. Sci. Ser. 4:238-241). All of these are from the southeastern quarter of the United States, except for the one species [rydbergiana](https://www.gallformers.org/gall/3396) in the mountains of northern New Mexico. Elsewhere in our Southwest and throughout most of Mexico the complex is replaced by the C. arida complex, and the relations of the two groups are so certain that we never expected to find the mellea complex in Mexico. It is, therefore, an item of some moment to have located a species of this Eastern American group south of the Rio Grande. 

  This Mexican species, sagata, comes from the northern end of the state of Coahuila, from just south of the Edwards Plateau of Central Texas. Further east in Mexico and in the southeastern corner of Texas, there is a great area of mesquite desert which is an absolute barrier to the interchange of eastern American and Eastern Mexican cynipid faunas. This oak-free area is about 350 miles wide. But there are, nevertheless, some instances of Eastern American affinities in the Eastern Sierra of Mexico; and it took a great deal of field work, spread over many years, to discover that there really are presentday connections between these two faunas. The complete story must be detailed elsewhere. Enough here to record that two of the Central Texan oaks, the live oak, Q. virginiana, and the scrub post oak, Q. breviloba, come close to the border in the neighborhood of Del Rio and a few points further west; that the live oak on the Mexican side is nearly continuous to the border in that same region; and that there is a taller tree (an undescribed species of oak) in the mountains of northernmost Coahuila which is so close to the Texan Q. breviloba that all of its cynipid fauna has Eastern Texan affinities. The present species, C. sagata, is the first of these breviloba relatives to be described from Coahuila. 

  One additional item of interest is involved in the fact that we have the present species, sagata, from this northern end of Coahuila, from both the Q. breviloba and from the Q. oblongifolia complexes. Oblongifolia is an oak of southern Arizona and northern Chihuahua. It is the only western oak that I have found in the northern end of the Eastern Sierra. Its presence there is probably due to the near approach of the Western and Eastern Sierra in northeastern Chihuahua and northwestern Coahuila. Nearly all of the cynipids on this oblongifolia relative in Coahuila have Western Sierran and Rocky Mountain affinities. The present instance of a cynipid with Eastern American affinities getting onto the western oak is a noteworthy exception to the rule. 

  The Central Texan species of the mellea complex is as yet undescribed. The galls of that Texan species and of the species from Coahuila are indistinguishable and, it is to be noted, rather distinct from the galls of the Eastern American species of the complex. These galls are, however, close to those made by C. (mellea) rydbergiana, which occurs in the northeastern corner of New Mexico (and adjacent Colorado ? ) ; and the insects of sagata and rydbergiana are closer than either species is to any of the Southeastern American species. In the key to the complex given in Kinsey 1930 (Ind. Univ. Studies 84-86:494- 495), this species sagata would run to rydbergiana.  The galls of the two are larger, more strictly spherical, smoother on the surface, and thicker-walled than the galls of any other described species. In all these characters, however, sagata is still closer to the Central Texan species from Q. breviloba. 


description:
  Cynips (nubila) lanaris, new species
  Agamic form

  GALL.—Central core red-brown, densely covered with short, hair-like cells most of which are swollen at tip. Long, hair-like spines forming body of gall light straw white, tinged yellow; bases of these spines almost never swollen; these spines wavy for their whole length and densely set. Galls appear as loose tangles of hairs. 

  HOST. — Quercus sacame [arizonica]. This is the largest tree among the evergreen white oaks of the region. 

  RANGE.—Tamaulipas: Miquihuana, 7 SE, 6000'. Possibly extending for some distance through a more northern end of the Eastern Mexican Sierra, east of the main divides. 

  LIFE HISTORY.—Adults ; December 10. 

  In our previously published revision of this complex (Kinsey, 1936, Ind. Univ. Sci. Ser. 4:243-258) we reported on nine species: two from southeastern Arizona, and seven from Mexico. Six of the Mexican species were from the Western Sierra and from the more southern Cordillera. Only one species, nigricula, was described from the Eastern Sierra—from the eastern part of San Luis Potosi. North of that point the Eastern and Western Sierras are widely separated, and this may explain the comparative rarity of the nubila complex in the Eastern mountains of Mexico. To the previously described list of species, however, we can now add two from this Eastern Sierra—one from northern Hidalgo, and one from southern Tamaulipas; but north of these norther- most localities there are still 400 miles of Eastern Sierra in which we have not found this group. 

  In the previously published key to this complex (Kinsey 1936:246- 247), the two species here described would run to sections 7 and 8; and the phylogenetic relations of the present species are clearly with incompta, nigricula, and chica, which appear in those sections of the key. This now gives us 5 species which have the parapsidal grooves continuous to the pronotum. As their geographic positions would lead one to expect, the present species are closest to nigricula and incompta. 

  We have lanaris from a locality near the southern end of the boundary between Tamaulipas and Coahuila. Lanaris is most closely related to the more southern species molucrum (described in the present paper). Lanaris differs chiefly in having the central core of the gall covered with hair-like cells, most of which are swollen at the tips. The galls of lanaris and nigricula are essentially the same. From incompta, lanaris is to be distinguished by the darker thoracic lines, the darker abdomen, and the vein-like form of the infuscation on the first abscissa. The galls of the two species are essentially the same.


description:
  Cynips (nubila) molucrum, new species
  Agamic form

  GALL.—Central core tan or brownish, densely covered with short, hair-like cells, none of which are swollen at tip ; lorg, hair-like spines forming body of gall light straw white, tinged yellow and still more golden tan near tips ; bases of these spines almost never swollen ; these spines wavy for their whole length, and densely set. Galls appearing as loose tangles of hairs. 

  HOSTS. — Quercus reticulata [rugosa] (types) ; Q. polymorpha. Large-leaved, evergreen, tree forms of white oaks. 

  RANGE.—Hidalgo: Jacala, •> W, 5000' (types on Q. reticulata. Also on Q. polymorpha). Probably widespread through a central portion of the Eastern Sierra of Mexico, ex- tending north from more northern Hidalgo. 

  This insect was collected along the Laredo-Mexico City highway, near Jacala, in the northern end of the state of Hidalgo. It may range more or less widely through the Eastern Mexican Sierra; but the complex is represented by the species nigricula in the Eastern Sierra of San Luis Potosi, and by the species lanaris, newly described in the present paper, from the northern end of the Eastern Sierra in Coahuila. The full extensions of these several ranges must, therefore, be determined by further collection. The characters of the present insect, molucrum, are closest to those of its nearest neighbors, C. incompta, C. lanaris, and C. nigricula (see Kinsey, 1936, Ind. Univ. Sci. Ser. 4:248, 251).

  The galls of molucrum differ (from those of incompta) in having the central core tan rather than brownish red; and the hair-like processes covering the central core are almost never swollen. The gall of molucrum differs from that of nigricula in having the central core tan (not red-brown), and practically none of the hairs covering this core show swollen tips. 

  From lanaris, molucrum differs principally in having the central core of the gall covered with short hairs which do not have swollen tips.


description:
  Cynips (plumbea) torosa, new species
  Agamic form

  GALL.—Large, spherical, rarely flattened on a small base, not pointed ; dull, slightly shrivelling, with a conspicuous, moderately heavy scurf (stellate pubescence) which is so persistent that even old galls are conspicuously bluish gray ; denuded surfaces of galls light tan to dark purplish brown; up to 9.5 mm., averaging near 7.0 mm. in diameter. 

  HOSTS. — Quercus rhodophlebia [rugosa] (types) ; Q. texcocana [deserticola]. These are the two largest trees among the oaks of the region. 

  RANGE.—Mexico : Mexico City, 22 E, 8200' (Q. rhodophlebia, Q. texcocana). Puebla: El Seco, 19 NE, 8500' (Q. rhodophlebia, types). El Seco, 5 SW, 8200' (Q. texcocana). Apparently restricted to the mountains east and southeast of Mexico City, ranging possibly into the state of Vera Cruz. Replaced south and west of Mexico City by C. texcocana Kinsey. 

  From several points in the mountains south and west of Mexico City we have C. (plumbea) texcocana (see Kinsey 1936, Ind. Univ. Sci. Ser. 4:205). From collections made 15 miles east of Mexico City, in January, 1932, we obtained three insects which look like good texcocana; but from the more extensive collections made 22 miles east of Mexico City in December, 1935, and from our collections made in the more south- eastern state of Puebla we get a different insect, the present species torosa. The galls of texcocana and torosa are practically identical, but the insects are so different that there seems no chance of error in our determinations; and we must conclude that the more eastern and more western species meet in the Valley of Mexico, or else that our earlier record for texcocana from east of Mexico City involved some error in data. We have several other cases of cynipid groups represented by different species on the two sides of the Valley of Mexico. 


description:
  Disholcaspis (cinerosa) pallens, new species

  GALL.—Practically identical with that of [Disholcaspis (cinerosa) cinerosa (Bassett)](https://www.gallformers.org/gall/814). Perhaps more often elongate and not as strictly spherical, more often drawn out to a slender point at base; averaging a bit smaller, up to 21.0 mm., mature galls averaging nearer 18.0 in diameter (Figure 2). 

  HOST. — Quercus oleoides. This narrow- and evergreen-leaved white oak is the common representative of the Q. virginiana complex in the northeastern portion of Mexico. 

  RANGE.—San Luis Potosi : Valles, 14 N, 900'. Probably confined to a central portion of the more eastern Mexican lowlands, iu- cluding the easternmost portions of the state of San Luis Potosi. 

  LIFE HISTORY.—Adults : December 7, 14, January 1, 7, 8, 17, 20. Two-thirds of the emergence over by the first of January, but goodly emergence continuing throughout most of January. 

  Two species of this complex have been previously described. The first, D. cinerosa (Bassett, 1881, Canad. Ent. 13:110) is widespread throughout the eastern two-thirds of Texas on the Texas live oak, Q. virginiana. Disholcaspis unicolor (Kinsey, 1920, Bull. Amer. Mus. Nat. Hist. 42:316) came from near Saltillo, in the northeastern part of Mexico. The present species, pallens, comes from a locality about 275 miles further south, halfway down the eastern Mexican coast and not far inland from Tampico. The locality, Valles, is on the Laredo-Mexico City highway. This is one of the relatively few cases of an Eastern American group having affinities in Eastern Mexico; for the host of the species, namely Q. oleoides of the Q. virginiana complex, belongs to one of the few groups of oaks which range without material interruption across the Rio Grande. An instance of a similar range on oaks of the Q. breviloba group is discussed under Cynips (mellea) sagata, newly described in the present paper. See sagata for a further discussion. 


description:
  Disholcaspis (mexicana) largior, new species
  Agamic form

  GALL.—Rosy to brownish tan, probably light and brighter when fresh, weathering darker brown ; inner faces of galls which are pressed against other galls in the clusters are smooth and shiny, but exposed surfaces are very much wrinkled, and conspicuously reticulate ; individual galls (in the rare instances where they occur singly) are more or less globose, but galls in compact clusters are very much compressed, making each one thin and flat with the exposed tops triangulate in outline ; a whole cluster therefore with a surface much like that of an unopened pine cone ; individual galls up to 24. mm. in diameter and 19. mm. in height; whole clusters up to 83. mm. in length and 44. mm. in diameter (Figure 4). 

  HOST. — Quercus rhodonplebia [rugosa], a large-leaved, evergreen white oak. Replaced on Q. chihuahuensis in the same area by Disholcaspis (mexicana) mexicana. 

  RANGE.—Pabellon, 20 W, 7000' (types). Probably restricted to> a portion of the Western Sierra of Mexico, including the mountains of the state of Aguascalientes. 

  LIFE HISTORY.—Adults: mature at some unrecorded date after November 26 (probably within the next few weeks). 

  We found this insect occuring in the same locality with Disholcaspis (mexicana) mexicana (Beutenmiiller), west of Pabellon, in the state of Aguascalientes; but largior was found on Q. rhodophlebia, while mexicana was found, in this region, on Q. chihuahuensis. The galls of the two are even more different, for the individual galls of mexicana, even in compact clusters, are more globose and smooth and shining; while those of largior are conspicuously wrinkled and so distorted that they show triangulate ends in their cone-like clusters.


description:
  Amphibolips fusus Kinsey

  Distribution: Zacatecas: Cantuna 

  Host: Quercus eduardi 

  Gall. A slender to globose, spindle-shaped oak apple, with the tip and base quite fine. A photograph of the gall was provided in Melika et al. (2011). 

  Life history. Unknown; only females reared from galls in November. 

  Comments This species was regarded by Melika et al. (2011) as very similar to A. zacatecaensis. However, the forewing patterns of the two species are quite different, which is a character that seems to be mistaken or overlooked by that authors. According to the coloration pattern of the forewing and shape of the gall, we consider this species to be more closely allied with the Panamanian species A. aliciae Medianero & Nieves-Aldrey 2010. One female that we reared from a globose, apically pointed gall collected in Nuevo León presented a similar forewing pattern (Fig. 21B) and could be identified as A. fusus, or more likely, a different closely allied species because of slight differences in the forewing patterns (Fig. 12F). However, other morphological characters are not well differentiated in this specimen, and it is not possible to come to a conclusion regarding its taxonomic status. We also collected galls similar to those of A. fusus in Monterrey and Nuevo León (Figs. 20E, 20F), but we unfortunately did not rear any adults from these galls. 


description:
  Amphibolips dampfi Kinsey

  Host: Quercus ocoteifolia, a synonym of Q. laurina

  Gall. A spongy oak apple similar to that of the American A. confluentus (Harris). More or less spherical, thin-shelled, spongy interior dense though soft, larvae central or nearer the base of the gall, galls up to 48 mm in diameter, detachable, on twigs. 

  Biology Bisexual; galls mature by February, and adults emerge between February and April

  Distribution: Oaxaca, Sierra Juarez


description:
  Amphibolips nassa Kinsey

  Gall: A rather large, globose but slightly spindle-shaped oak apple with a fine tip and base. Body of gall quite globose. A photography of the gall was provided by Melika et al. (2011). 

  Distribution: Michoacán, Purépero on Quercus mexicana and Q. castanea (= Q. serrulata). 

  Comments Based on its forewing pattern and gall, A. nassa is very similar to the recently described Amphibolips zacatecaensis Melika & Pujade-Villar 2011. The galls of A. nassa and A. zacatecaensis are quite similar, but Melika et al. (2011) noted that the galls of A. nassa are more elongate and fusiform, with a hard lignified parenchyma, while the galls of A. zacatecaensis are globose, with a soft spongy parenchyma. After our analysis, we consider A. nassa to be more similar to the new species A. oaxacae described here, with the two species being differentiated by their coloration, relative emargination of the mesoscutellum and shape of the gall. 


description:
  Amphibolips palmeri Basset 1890

  This species is cited as the largest known species of gall fly and “oak apple gall” (Beutenmüller 1909). It was described from materials collected in Sierra Madre, Chihuahua, and Guadalajara, Jalisco, Mexico. This species was apparently overlooked by Kinsey in his work addressing the Amphibolips of Mexico (Kinsey 1937).

  It was not possible to find the type material. However, we reproduce the description provided by Beutenmüller (1909), which is diagnostic with regard to the forewing colour pattern. 

  Gall. Produced on twigs of an unidentified Quercus species [Quercus mexicana added as a placeholder]. Spherical, with a wrinkly surface with a few scattered very short projections. Internally, the gall is of a spongy consistency. A central rounded larval cell is embedded in the soft internal tissue. 

  Comments. According to Melika et al. (2011), this species may be a synonym of A. dampfi. In our opinion, however, although the galls of the two species are similar, the descriptions of the forewing colour patterns of the two species are not in accordance. Thus, we maintain the status of A. palmeri as a good species


description:
  Amphibolips hidalgoensis Pujade-Villar & Melika 2011

  Distribution: Hidalgo state 

  [Photos of this gall appear on page 36 of the pdf]

  Gall (Figs 18A, 18B). Spherical, diameter up to 6.5 cm, thin walled, with a smooth and naked surface a with soft, spongious parenchyma and radiating filaments supporting the single central larval cell (Melika et al. 2011). 

  Host: Quercus crassipes and Q. crassifolia 

  Life history. Only females are known. According Melika et al. (2011), they may represent the asexual generation

  Amphibolips malinche sp. nov.

  Gall (Figs 19C, 19D). A globular, irregular oak apple gall. Monothalamic; outer shell thin and internally exhibiting a spongy consistency, filling the entire gall. Found on twigs of Quercus mexicana.

  Distribution. A. malinche was found at 2800 m a.s.l. at La Malinche volcano, Tlaxcala state, Mexico.

  Biology. Presumably a sexual generation, but males were not reared. The galls were collected in late June, and the insects emerged in July.


description:
  Amphibolips zacatecaensis 

  [A photo of this gall appears on page 36 of the pdf]

  Because the two species [zacatecaensis and [Amphibolips fusus](https://www.gallformers.org/gall/2559)] share morphologically similar galls, the only difference between them may be the inner consistency of the gall, which presents a soft, spongious parenchyma, whereas it is hard and lignified in A. nassa (Melika pers. comm.).

  Distribution: Zacatecas state 

  Gall. Large, globose to slightly spindle shaped, with a nipple at the top (Fig. 18E). The gall is thin walled, very lightweight, internally showing a soft spongious consistency. Internally, the gall exhibits a single hard-walled central larval cell (Melika et al. 2011). 

  Host. Quercus eduardi 

  Life History. Unknown


description:
  Amphibolips durangensis sp. nov. [both durangensis and duraguensis appear in the description]

  [Photos of this gall appear on page 36 of the pdf]

  Gall (Figs.18C, 18D). A spindle-shaped gall with an elongated and narrow tip and base. Longitudinally, the surface of the gall is crossed by longitudinal ridges. The gall is monothalamic; the outer shell is thin but firm; internally, it has a spongy consistency, filling the entire gall (Fig. 18D). The larval cell is rounded and is embedded in the soft internal substance. Diameter of 54 x 43 mm on average). Forms on twigs of Quercus scytophylla. The gall closely resembles that of Amphibolips fusus Kinsey 1937, also described from Mexico, and was illustrated recently by Melike et al. (2012). However, the gall of A. duranguensis differs from the gall of A. fusus due to its much more elongated and narrow points, both at the tip and at base. Another difference is the gall surface, which is smooth in the gall of A. fusus, without longitudinal ridges. 

  Distribution. A. duranguensis was found at 1900 m a.s.l. in Durango state, Mexico. 

  Biology. Only females of the presumably sexual generation are known. The galls were collected in July, and the insects emerged in October. 


description:
  Amphibolips jaliscensis sp. nov.

  Gall (Figs 19A, 19B). A globular oak apple gall. Monothalamic; outer shell thin and internally showing a spongy consistency, filling the entire gall. Grows on twigs of Quercus sp. aff candicans. 

  Distribution. A. jaliscensis was found at 2370 m a.s.l. at Jalisco state, Mexico.

  Biology. Exhibits a sexual generation; both males and females are known. The galls were collected in late March, and the insects emerged in April. 


description:
  Amphibolips oaxacae sp. nov.

  [A photo of this gall appears on page 36 of the pdf]

  Gall (Fig. 18F). A regularly spherical, large oak apple gall measuring approximately 40 mm in diameter. Pale green with darker green spots when fresh. The gall is monothalamic; the outer shell is thin but firm; with a spongy consistency internally, filling the entire gall. The larval cell is rounded and is embedded in the soft internal substance. Forming on twigs of Quercus sp. aff sapotifolia. The gall closely resembles that of Amphibolips palmeri Basset 1890, also described from Mexico, but for which the host is unknown. 

  Distribution. A. oaxacae was found at 1180 m a.s.l. in Oaxaca State, Mexico. 

  Biology. Only females of the presumably sexual generation are known. The galls were collected in March, and the insects emerged in the same month. 


description:
  Amphibolips nevadensis sp. nov.

  Gall (Figs 19E, 19F). A globular gall ending in a obtuse apical point. Monothalamic. Grows on twigs of Quercus candicans. 

  Distribution. A. nevadensis was found at 2300 m a.s.l. at Nevado Colima, Jalisco state, Mexico. 

  Biology. Exhibits a sexual generation. The galls were collected in March, and the male adults emerged in April. The female was collected in August


description:
  Amphibolips tarasco sp. nov.

  [Photos of this gall appear on page 38 of the pdf]

  Gall (Figs 20C, 20D). A large, regularly spherical, oak apple gall. The surface of gall is smooth, green with darker green spots when fresh. Monothalamic. Grows on twigs of Quercus castanea. 

  Distribution. A. tarasco was found at 2000 m a.s.l. at Santa María, Michoacán state, Mexico. 

  Biology. Includes a sexual generation. The galls were collected in March, and the adults emerged shortly after the galls were collected.


description:
  Amphibolips michoacaensis sp. nov.

  [Photos of this gall appear on page 38 of the pdf]

  Gall (Figs 20A, 20B). A globular more or less regular gall with spongy interior Monothalamic. Grows on twigs of Quercus castanea or nearer the base of the gall, galls up to 48 mm in diameter, detachable, on twigs. 

  Distribution. A. michoacaensis was found at Umécuaro and other sites of Cuenca of Cuitzeo at 2100 m at Michoacán state, Mexico. 

  Biology. Exhibits a sexual generation. The galls were collected in April, and the adults emerged in May.


description:
  Amphibolips nassa

  [Photos of this gall appear on page 12 of the pdf]

  in A. nassa, the gall is more elongate, spindle-shaped, with hard, lignified parenchyma


description:
  Amphibolips aliciae 

  [Photos of this gall appear on page 39 of the pdf]

  Galls of A. aliciae are fusiform, fragile onto smallest pressure, internal hollow-like space with thin filaments radiating from the central larval chamber (Figs 14B, 14D); while galls of A. kinseyi n. sp. and A. quercuspomiformis comb. nov. are subglobose, hard, with internal space obliterated by a spongious parenchyma. The internal structure of A. aliciae gall also resembles the gall of A. salicifoliae, which are hollow with radiating filaments. However, they can be differentiating by the shape and gall location: fusiform galls on buds in A. aliciae and spherical galls on leaves in A. salicifoliae. 

  Gall (Figs 14A–D). A fusiform bud gall with a fine tip and base, with a hard, lignified outer shell, 2.5 mm long. Internal space hollow with thin filaments radiating from the central larval chamber, 5–6 mm in diameter. 

  Hosts. Quercus salicifolia (Panama); Q. crassifolia (Mexico, new record). 

  Biology. Only the sexual generation is known. Galls were collected from January to March; adults emerged shortly after gall collecting. Distribution. Panama (original description), Mexico: Puebla state, new record.


description:
  Amphibolips bassae n. sp.

  [Photos of this gall appear on page 44 of the pdf]

  Gall (Figs 16E–G). A rather small, subglobose bud gall, around 40 mm in diameter; slightly narrower at base around the connection with the branch. The gall is thick-walled, with lignified parenchyma, olive green when mature and turn light brown when dry, with smooth and naked surface; hard spongious parenchyma internally with central ovate, hard-walled larval chamber, with largest length of 5.0–6.5 mm. 

  Host. Quercus crassifolia. 

  Biology. Only the sexual generation is known. The mature gall was collected in May; adults emerged in June. 

  Distribution. Mexico: Puebla State


description:
  Amphibolips bromus, n. sp.

  [Photos of this gall appear on page 39 of the pdf]

  Gall (Fig. 14H). A very thin and elongate bud gall, about 50 mm long, with greatest width near the middle, up to 4 mm wide; elongate and thin petioles widening near median part, pointy apex gradually tapering from middle part. The gall is thin-walled, with a smooth and naked surface; thin spongious layer internally surrounding the central ovate larval chamber, with mature galls having a length of 5.0–6.5 mm. 

  Hosts. Quercus affinis, Q. crassipes. 

  Biology. Only the females are known. The mature gall was collected in May; adults emerged by the end of May. 

  Distribution. Mexico: Hidalgo and Mexico States.


description:
  Amphibolips castroviejoi

  Galls of A. castroviejoi are differ from all other known galls; they are large (on average 54 x 43 mm), irregularly spherical or globose, elongated at the base, with a thick peduncle, without apical tip, and with a smooth, mottled surface. 

  Gall. A globose bud gall, 45–58 mm in diameter, with short elongation at the base forming a thick peduncle. Light green and mottled when mature, turning light brown when dry. Outer shell thin, hard. Internal parenchyma soft and spongious. Central larval chamber with a hard shell, 5–6 mm in diameter. A picture of the gall is given in Medianero & Nieves-Aldrey (2010: Figs 8A–C). 

  Host. Quercus salicifolia. 

  Biology. Only the sexual generation is known. Galls were collected in January; adults emerged in February. 

  Distribution. Panama


description:
  Amphibolips cibriani

  [Photos of this gall appear on page 39 of the pdf]

   The gall also differs from all other known galls from Mexico and Central America (see below). 

  Gall. (Figs 14I–K) A subglobose bud gall, approximately 20 mm in diameter. Outer shell lignified and hard. Surface rugulose, uniformly light brown, with short apical tip and peduncle. The gall is monolocular, with a spongy internal tissue, filling the entire gall, with central rounded larval cell. 

  Host. Quercus crassipes.

  Biology. Only females are known. The galls were collected in April; adults emerged in May. 

  Distribution. Mexico: Ciudad de México State


description:
  Amphibolips dampfi Kinsey

  [Photos of this gall appear on page 43 of the pdf]

  This species highly resembles A. turulli n. sp. (see below) especially for the similar mesoscutellum and forewing colour pattern; but in A. dampfi the area laterad to parapsidal lines rugose (alutaceous in A. turulli n. sp.); forewings with anal and basal half of discoidal cells completely infuscate (hyaline in A. turulli n. sp.), fragile subglobose internally spongious bud galls slightly pedunculate and with small tip at apex with internal spongious tissue soft, mainly white turning into roseate around larval cell, light brown when dry (turgescent green leaf galls in A. turulli n. sp.). The gall of A. dampfi is unmistakable. It is very deformable for its lax and soft spongy internal tissue with a cotton-like appearance. It resembles A. zacatecaensis gall but in A. dampfi the internal tissue is white to rosy near the larval chamber, very soft, cotton-like (light brown and denser in A. zacatecaensis). 

  Gall (Fig. 15E). Monolocular subglobose bud gall, up to 50 mm in diameter, with slightly elongate apex and base with smooth and fragile surface, homogenous in colour; internal spongious tissue soft, white to rosy, turning brown when dry; with cotton-like texture (the fibers leaving numerous aerial interspaces); larval chamber occupying central part of the gall, about 4–5 mm in diameter, embedded with spongious tissue.

  Hosts. Quercus ocoteifolia, Q. affinis. 

  Biology. Only the sexual generation is known. Galls mature by February and March; adults emerge from February to April 

  Distribution. Mexico: Hidalgo and Oaxaca states. 

  Remarks. The name of the host plant (Q. ocoteifolia), cited in the original description of this species, was erroneously written as Q. ocoteaefolia. This incorrectly spelled epithet appeared in a number of infraspecific descriptions: Quercus ocoteaeifolia f. confusa Trel., Q. laurina var. ocoteaefolia (Liebm.) Wenz., and Q. nitens var. ocoteaefolia (Liebm.) A. DC. All those forms and varieties were synonymized under Q. ocoteifolia. 

  Comments. According to Melika et al. (2011) A. dampfi closely resembles A. palmeri Basset 1890 and may be synonymous. The type of A. palmeri (a single female) is lost, nevertheless the adult and gall descriptions seem to be consistent with this hypothesis (see A. palmeri below). The type of A. dampfi is also presumed to be lost (C. Le Beau pers. comm.).


description:
  Amphibolips durangensis

  The gall of this species closely resembles A. fusus, differs by the elongation of both, peduncle and apical tip, thinner in A. durangensis; surface of galls is crossed by longitudinal ridges in A. durangensis and smooth in A. fusus.

  Gall. Galls on buds, fusiform, maximum 43–54 mm in diameter, with elongate thin peduncle and apical tip; outer shell thin, hard, usually smooth with longitudinal ridges; internal spongious soft tissue with central larval chamber, around 5 mm (Nieves-Aldrey et al. 2012: Figs 18C–D). 

  Host. Quercus scytophylla. 

  Biology. Only females are known. The mature galls were collected in early July; adults emerged in October. 

  Distribution. Mexico: Durango State


description:
  Amphibolips fusus

  [A photo of this gall appears on page 39 of the pdf]

  Galls of A. fusus greatly differ from the galls of the other mentioned species. However, galls most closely resemble galls of A. durangensis, but differ by the smooth and even surface in A. fusus (with transversal ridges in A. durangensis), and both the peduncle and apical tip narrow gradually in A. fusus (peduncle and apical tip highly narrowed into acicular projections in A. durangensis). 

  Gall (Fig. 14E). Monolocular bud gall. Fusiform, 9–13 mm in diameter, with a peduncle and a fine tip. Outer shell thick, hard, light brown when mature, with smooth glabrous surface, without mottled surface. Internal tissue relatively soft and spongy; made up of dense irradiating fibers visible only at the base and apex; dense and compact at the central body of the gall where the space is mostly occupied by the larval chamber. Central, oval larval chamber (5.0–6.0 mm) relatively hard-walled. 

  Hosts. Quercus eduardi (original description) and new records on Q. crassipes and Q. laurina here. 

  Biology. Only females are known. The mature galls were collected in early June; adults were extracted dead in November (according to the original description); no adults were found in the newly collected galls. 

  Distribution. México: Ciudad de México, and Zacatecas states. 

  Remarks. Kinsey’s original description states that this species has POL 1.3x as long as OOL. Despite being true in the holotype, POL is equal to OOL in the new specimens that were reared from similar galls, on the same host plant. We attribute this difference to the intraspecific variability considering that no additional differences were detected. Nieves-Aldrey et al. (2012) differentiated this species based on the forewing colouration and F1 being 1.2x as long as F2. These characters became inaccurate to discriminate A. fusus, due to the discovery of additional species, described in this paper, possessing the same character states: A. cibriani Pujade-Villar 2018, A. bassae n. sp. and A. bromus n. sp. (see above)


description:
  Amphibolips hidalgoensis 

  [Photos of this gall appear on page 43 of the pdf]

   This species closely resembles [A. tarasco](https://www.gallformers.org/gall/3777). Galls of both species are subglobose bud galls, but A. hidalgoensis has galls with a thin, uniformly coloured outer shell and soft spongious internal tissue, while galls of A. tarasco have a mottled surface and outer shell and internal spongious tissue that is rather hard (Figs 16H–I). The gall is similar to other species with a large globular shape without a mottled surface; it is not differentiable from A. michoacaensis and A. jaliscensis, but differs from A. quercuspomiformis comb. nov., A. oaxacae, A. tarasco, A. kinseyi n. sp. and A. bassae n. sp. by having a deformable surface under applied finger pressure, because the parenchyma is relatively soft in A. hidalgoensis, A. jaliscensis and A. michoacaensis. 

  Gall (Figs 15A–B). Usually large, subglobose, detachable bud galls, sometimes with fine tip at apex. Maximum diameter 30–65 mm. Outer shell thin and fragile; internal tissue spongious and soft with central larval chamber about 5 mm in diameter. 

  Hosts. Quercus acutifolia, Q. calophylla, Q. castanea, Q. crassifolia, Q. crassipes, Q. mexicana. 

  Biology. Only females are known. We consider this species to be an asexual form as we have never obtained males after the emerging of more than 100 females from different localities. The mature galls were collected in late May to early June; most adults emerged soon after field collection, some were reared in November. 

  Distribution. Mexico: Hidalgo, Mexico and Tlaxcala states. 

  Remarks. After the examination of A. malinche types, we found great similarities between this species and A. hidalgoensis. Furthermore, the galls of both species are identical. Amphibolips malinche were sampled in the state of Tlaxcala and numerous specimens of A. hidalgoensis were collected 30 km away from the location of the two known specimens of A. malinche. The two specimens of A. malinche reared from galls of Q. mexicana, which shares distribution with the rest of host plant species (Q. calophylla, Q. crassifolia and Q. crassipes) in the states of Ciudad de México, Guanajuato, Hidalgo, México, Oaxaca, Puebla, Querétaro. This species is currently the only one known to have such a wide range but no correlation with other characters has been found. Amphibolips hidalgoensis is by far the most frequently collected Amphibolips species in Mexico. Such sampling bias might be concealing other, poorly sampled, species’ variability and attributing as intraspecific variability to a possible widely spread interspecific common trait. Alternatively, A. hidalgoensis is probably a complex of species that cannot be sorted out by only morphological criteria. For all these reasons we consider A. malinche as a syn. nova of A. hidalgoensis.


description:
  Amphibolips jaliscensis 

  Galls of A. jaliscensis and A. michoacaensis are subglobose, outer shell thin and rather fragile with uniform colouration (pale green in A. jaliscensis and whitish in A. michoacaensis), with spongious parenchyma internally, the gall turning brown when dry. Galls of A. nevadensis are different for its distinct apical tip. Amphibolips jaliscensis gall is similar to other species with large globular shape, without mottled surface; it is not differentiable from A. hidalgoensis and A. michoacaensis, but differs from A. quercuspomiformis comb. nov., A. oaxacae, A. tarasco, A. kinseyi n. sp. and A. bassae n. sp. in having a deformable surface at finger pressure because the parenchyma relatively soft in A. hidalgoensis, A. jaliscensis and A. michoacaensis. 

  Gall. Spherical bud galls, maximum diameter 43–54 mm; outer shell thin, firm, surface smooth with uniform pale green colour turning into brown when dry; internal tissue soft and spongious, with central larval chamber around 5 mm (Nieves-Aldrey et al. 2012: Figs 19A–B). 

  Hosts. Quercus aff. calophylla (= Q. aff. candicans), Q. laurina. 

  Biology. The sexual generation is only known. The mature galls were collected in late March; adults emerged in April and May. 

  Distribution. Mexico: Jalisco and Mexico states. 

  Remarks. This species is difficult to differentiate from A. michoacaensis, except for two scutellar characters. This fact leads us to suspect that they might be the same species. 


description:
  Amphibolips michoacaensis

  The large globular gall is similar to other species, with or without mottled surface (Nieves-Aldrey et al. 2012: Figs 20A–B); impossible to differentiate from A. hidalgoensis and A. jaliscensis but differs from A. quercuspomiformis comb. nov., A. oaxacae, A. tarasco, A. kinseyi n. sp. and A. bassae n. sp. by the deformable surface at finger pressure because of the relatively soft parenchyma in A. hidalgoensis, A. jaliscensis and A. michoacaensis. 

  Gall. A subglobose large bud gall, up to 48 mm in diameter, outer shell thin but resistant, uniformly pale green, turning into brown when dry. The gall is monolocular, with a spongy internal tissue, filling the entire gall. The larval cell is rounded (Nieves-Aldrey et al. 2012: Figs 20A–B). 

  Host. Quercus castanea, Q. emoryi. 

  Biology. Only the sexual generation is known. Galls were collected between April and May; adults emerged between May and October of the same year of collection. 

  Distribution. Mexico: Michoacan and Zacatecas states. 

  Remarks. Nieves-Aldrey et al. (2012) described the males with 12 flagellomeres, however, the antenna has 13 flagellomeres (type specimens examined). This species shares several characters with A. jaliscensis, including the forewing pattern, that were originally used as diagnostic (Nieves-Aldrey et al. 2012), and the gall morphology is also similar between the two species (see corresponding remarks under A. jaliscenis).


description:
  Amphibolips nassa

  [Photos of this gall appear on page 43 of the pdf]

   Amphibolips nassa closely resembles A. zacatecaensis but differs in . . . and galls (A. nassa are subglobose, but a bit fusiform with a tip and a base, with lignified spongious parenchyma while in A. zacatecaensis galls are fragile, globose with a tiny tip at apex, with soft spongious parenchyma. The galls are very similar to A. nevadensis and A. rulli n. sp. ; galls of these species cannot be differentiated, only by the uniformly brown surface of the galls of A. nassa (mottled in A. nevadensis and A. rulli n. sp. ), and the host plants are different; Amphibolips nassa in buds of Q. castanea, A. nevadensis galls on Q. calophylla and A. rulli n. sp. on Q. eduardi and Q. viminea. All these galls are subglobose, hard and with an apical tip, resulting from the longitudinal elongation of the gall. 

  Gall (Figs 15F–G). A rather large, subglobose, slightly fusiform, elongated bud oak apple, up to 48 mm in diameter, detachable, with a fine tip and base; with hard, lignified parenchyma. Larval chamber central or near the base of the gall, on buds. Host. According to the original description, Q. castanea. 

  Biology. Galls were collected in December; the only known adult was dissected out of the gall. 

  Distribution. Mexico: Michoacán state. 

  Remarks. Kinsey (1937) mentioned that similar galls were collected in the same place on Q. mexicana by Morelia from the same host plant as the holotype, but after knowing that different species are found in similar galls, we cannot assure this citation was correct


description:
  Amphibolips nevadensis

  Galls are very similar to those of A. nassa and A. rulli n. sp.; these species cannot be differentiated by galls, only by the host plant; Amphibolips nevadensis on Q. calophylla, A. nassa on Q. castanea and A. rulli n. sp. on Q. eduardi and Q. viminea. All these galls are subglobose, very hard and fusiform at apex, ending in a defined tip. 

  Gall. A subspherical bud gall, fusiform at apex, ending in a tip, maximum 40 mm in diameter, outer shell thin, resistant, slightly lignified. Olive green with pale green spots when fresh and turning dark green when dry. The gall is monolocular, with a spongy internal tissue, filling the entire gall. The larval cell is rounded. Pictures of the gall are provided in Nieves-Aldrey et al. (2012: Figs 19E–F) 

  Host. According to the original description, Q. calophylla (= candicans). We found galls on the same host plant. 

  Biology. Only females are known. The galls were collected in March; adults emerged in the same month. 

  Distribution. Mexico: Jalisco State. 


description:
  Amphibolips oaxacae

  The globular gall resembles others but galls of A. oaxacae and A. tarasco are hard, around 40 mm in diameter, not deformable at finger pressure, with mottled surface. Both species cannot be differentiated by galls shape, only by the host plant: A. oaxacae galls on Quercus sp. aff. sapotifolia, A. tarasco galls on Q. castanea. 

  Gall. A subglobose large bud gall, maximum 40 mm in diameter, outer shell thin, resistant, slightly lignified. Pale green with darker green spots when fresh and turning brown when dry. The gall is monolocular, with a spongy internal tissue, filling in the entire gall; the larval cell is rounded (Nieves-Aldrey et al. 2012: Fig. 18F). 

  Host. Quercus sp. aff. sapotifolia (according to original description). 

  Biology. Only females are known. The galls were collected in March; adults emerged in the same month. Distribution. Mexico: Oaxaca State. 

  Remarks. Most closely resembles A. tarasco. Only one specimen of A. oaxacae is known and until more material is found it is impossible to sort out the intraspecific variability in this species. However, the actual differences that determine A. oaxacae are robust enough to consider it as a valid species. 


description:
  Amphibolips palmeri species dubia

  The type material is presumably lost (Buffington pers. com.). 

  This species was described from a single specimen extracted from a gall collected from an unidentified Quercus species by Basset (1890). According to the author, the gall was donated by Mr. B. Pickman Mann and had the following label: “Summit of Sierra Madre, Chihuahua, México. Winter 1885–86, Dr. Edward Palmer”. Beutenmüller (1909) in his revision of the Amphibolips of North America broadened the distribution of this species to Guadalajara (Jalisco, México) for a gall deposited in the American Museum of Natural History, but did not add any new information to the description of the species. Amphibolips palmeri was not mentioned in Kinsey (1937) paper on Amphibolips of México. 

  In the latest studies on Amphibolips (Melika et al. 2011; Nieves-Aldrey et al. 2012) as well as in this study, the type material of the species was not found. Concerning to the gall, it is a large spherical spongious bud gall. Light yellowish brown; the outer shell thin but firm. Internally soft spongious tissue. Larval chamber round embedded in the spongious tissue. Diameter: 35 to 70 mm. 

  Remarks. According to Melika et al. (2011), this species closely resembles A. dampfi and might well be synonymous. The type (female) of A. palmeri is lost, nevertheless the adults and galls descriptions are consistent. For the moment, this species is considered as species dubia until the type material appears, or new data can be examined. 


description:
  Amphibolips quercuspomiformis comb. nov.

  [Photos of this gall appear on page 44 of the pdf]

  Cynips q. pomiformis Bassett, 1881: 74.
  Andricus (Andricus) pomiformis (Bassett) Ashmead, 1885: 295
  Callirliytis rossi Kieffer, 1903: 84. Synonymy in Weld, 1951: 652
  Callirhytis maculipeunis Kieffer, 1904: 131. Synonymized by Kinsey, 1922: 36
  Andricus yosemite Beutenmuller, 1911: 211. Synonymy in Weld, 1951: 652
  Callirhytis pomiformis (Bassett) Mayr, 1902: 289
  Andricus pomiformis var maculipennis (Kieffer) in Kinsey, 1922: 36
  Callirhytis quercuspomiformis (Bassett), Weld, 1951: 652

  Gall. Asexual galls (Figs 16A–D). A large multilocular subglobose bud gall, up to 40 mm in diameter. The body of the gall is spherical (rarely flattened or ovate), with greatest diameter near the middle of the gall; surface sometimes with low tubercles radiating more or less from the slightly pointed tip of the gall. The gall is hard-walled, yellowish to rufous-magenta when mature and turning to brownish orange when dry, with smooth and naked surface; spongious internally, with hard filaments connecting the larval chambers with the base of the gall; up to 50 hard-walled larval chambers clustered in the center of the gall, easily separable from the firm; sometimes resembling the inquiline larval chambers; each larval chamber around 2.0–4.0 mm in diameter. 

  Hosts. Quercus agrifolia, Q. wislizenii, for both generations. 

  Biology. Alternate sexual and asexual generations are known (Lyon 1959). Sexual galls appear from February to early April, mature in early May; adults emerged from mid-May to the first week of June. Asexual galls mature in October; adults emerged in November. 

  Distribution. USA (California) and México (Baja California and Guanajuato states). 

  Remarks. Kinsey (1922) named this species as Andricus pomiformis and described five varieties, considering Callirhytis maculipennis Kieffer 1904 one of them: A. pomiformis var descansonis (Kinsey 1922), A. pomiformis distinctus (Kinsey 1922), A. pomiformis pomiformis (Basset, 1881), A. pomiformis var maculipennis (Kieffer) and A. quercuspomiformis provincialis (Kinsey 1922). Later, Weld (1951), following Mayr’s work (1902), transferred this species to the genus Callirhytis and recognised only three of Kinsey’s varieties (var. descansonis, var distincta and var. provincialis). Later, Melika & Abrahamson (2002) concluded that this species belongs to the genus Amiphibolips but did not formalize the nomenclatorial act for species transfer. Herein this nomenclatorial act is completed. According to Kinsey (1922), the morphological differences of these varieties included . . . the gall surface (present several projections on the surface, each ending in a short filament in var. distinctus and surface smooth and naked in the rest). Among the varieties, the most deviant is var. distinctus based on the distinct notauli, median sulci visible and the surface of the galls with projections. However, Kinsey (1922) comments that some var. distinctus specimens share characters of var. maculipennis (as well as var. provincialis had specimens similar to var. maculipennis). Similarly, the new material from Baja California present distinct notauli, smooth notaular furrow posteriorly as in var. distinctus, but the median sulci and scutellar posteromedian depression are absent, and the speculum is completely smooth and glabrous. The distribution of the varieties is limited to California (USA) and range from the central to southern regions. All varieties have overlapping, or nearly so, distributions with at least another variety. The range of var. maculipennis includes localities from the range of var. descansonis, var. distinctus and var. provincialis, which occur almost exclusively in the southern regions. The variety pomiformis is limited to central California (San Francisco, Mount Diablo, Gilroy, and Salinas) and the closest known varieties are var. maculipennis and var. distictus (Yosemite Park and Merced Falls). Most of these characters also follow a continuous variation, and the distributions overlap in the southern regions for all, except var. pomiformis. Thus, there are not conspicuous character states to support these varieties as independent entities. Also, the host plant is Q. agrifolia in three of the varieties and Q. wislizenii in var. provincialis and var. distinctus. Both oaks are closely related and often form hybrids (Brophy & Parnell 1974). We consider all these varieties as intraspecific variations of Amphibolips quercuspomiformis comb. nov.


description:
  Amphibolips quercuspomiformis comb. nov.

  Cynips q. pomiformis Bassett, 1881: 74.
  Andricus (Andricus) pomiformis (Bassett) Ashmead, 1885: 295
  Callirliytis rossi Kieffer, 1903: 84. Synonymy in Weld, 1951: 652
  Callirhytis maculipeunis Kieffer, 1904: 131. Synonymized by Kinsey, 1922: 36
  Andricus yosemite Beutenmuller, 1911: 211. Synonymy in Weld, 1951: 652
  Callirhytis pomiformis (Bassett) Mayr, 1902: 289
  Andricus pomiformis var maculipennis (Kieffer) in Kinsey, 1922: 36
  Callirhytis quercuspomiformis (Bassett), Weld, 1951: 652

  Gall. Sexual galls. A toadstool-shaped gall arising singly, or occasionally in groups of two or three from the lamina of the underside of the leaves. Galls are tinged with rose or pink when young, although most are light-green in colour. Galls are monolocular, with the single cell occupying the space below the flared top of the gall. The elongated stem of the gall is solid. 

  Hosts. Quercus agrifolia, Q. wislizenii, for both generations. 

  Biology. Alternate sexual and asexual generations are known (Lyon 1959). Sexual galls appear from February to early April, mature in early May; adults emerged from mid-May to the first week of June. Asexual galls mature in October; adults emerged in November. 

  Distribution. USA (California) and México (Baja California and Guanajuato states). 


description:
  Amphibolips rulli n. sp.

  [Photos of this gall appear on page 43 of the pdf]

  Gall (Figs 15H–I). A subspherical, bud gall, fusiform at apex, ending in a tip, with greatest diameter near middle of the gall, up to 35 mm in diameter. The gall is thin-walled, olive green, mottled with clear spots when mature and turn brown when dry, mottles still visible; parenchyma rather lignified, rugose; internal tissue hard spongious, with central ovate hard-walled larval chamber, with mature length 5.0–6.0 mm. 

  Hosts. Quercus eduardi, Q. emoryi, Q. viminea. 

  Distribution. Mexico: Zacatecas State. 

  Biology. Only females are known. Mature galls were collected in October; adults emerged in November


description:
  Amphibolips salicifoliae

  Galls of A. salicifoliae are subglobose, on the underside of leaves, very fragile, outer shell thin, hollow internally with thin filaments radiating from larval chamber while galls of A. quercuspomiformis comb. nov. are on buds, with outer shell hard, internal parenchyma spongious. Thin filaments radiating from the larval chamber to the outer shell in A. aliciae. We can differentiate these galls by the shape of the gall and its location (fusiform bud galls in A. aliciae and spherical leaf galls in A. salicifoliae).

  Host. Quercus salicifolia. 

  Gall. Globose and fragile galls on the underside of leaves, with maximum diameter 30 mm; outer shell thin, internal space hollow with filaments radiating from the larval chamber. Larval chamber central or at the base of the gall (Medianero & Nieves-Aldrey 2010: Figs 8G–H). 

  Biology. The sexual generation is only known. Galls were collected in January; adults emerged in February. 

  Distribution. Panama.


description:
  Amphibolips tarasco

  [Photos of this gall appear on page 44 of the pdf]

  Gall (Figs 16H–I). A subglobose large bud gall, with maximum 40 mm in diameter, with thin, slightly lignified and resistant outer shell. Pale green with darker green spots when fresh and turning brown when dry. The gall is monolocular, with a spongy internal tissue, filling the entire gall. The larval cell is rounded. 

  Hosts. Quercus acutifolia, Q. castanea, Q. mexicana. 

  Biology. The sexual generation is only known. The galls were collected between March and June; adults emerged in the same months of collection. 

  Distribution. Mexico: Michoacán and Puebla States.


description:
  Amphibolips turulli n. sp.

  [Photos of this gall appear on page 39 of the pdf]

  Gall (Figs 14F–G). A turgescent spherical gall located on the underside of leaves. The body of the gall is globose, with greatest diameter near middle of the gall measured from base to apex, up to 20–25 mm. The gall is thin-walled, olive green when mature and turns wrinkled when dry, with smooth and naked surface, succulent, with central ovate hard-walled larval chamber, with largest length of 5.0–6.5 mm. 

  Hosts. Quercus affinis. 

  Biology. Only females are known. The mature galls were collected in late June; adults emerged in early July. 

  Distribution. Mexico: Hidalgo State. 

  Remarks. The gall of this new species is not usual for Mexican Amphibolips species, but two North American species have similar galls on the underside of leaves: A. quercusracemaria (Ashmead, 1881) from Florida (USA) on Q. laurifolia and A. nubilipennis (Harris, 1841) from Massachusetts on several species of red oaks. Nevertheless, the sculpture of the mesoscutum and the colour pattern of wings are different in A. quercusracemaria and A. nubilipennis


description:
  Amphibolips zacatecaensis

  [Photos of this gall appear on page 43 of the pdf]

  The gall resembles that of A. dampfi, but in A. zacatecaensis the internal tissue is dense and light brown while it is soft, cotton-like, white to rosy near the larval chamber in A. dampfi. 

  Gall (Figs 15C–D). Galls on buds, rather large, with maximum diameter 50–68 mm, subglobose, gradually tapering to a tip at apex; outer shell thin and fragile, usually smooth, sometimes wrinkled or rugose; internal tissue soft, light brown and spongious, but consistent with central larval chamber, which is around 5 mm in diameter. 

  Host. Quercus eduardi. 

  Biology. Only females are known. The mature galls were collected in late May; adults emerged soon after field collection. 

  Distribution. Mexico: Zacatecas State


description:
  Amphibolips palmeri

  Gall. On the terminal small twigs of a species of oak (Quercus sp). Monothalamous, round, with the surface uneven, or somewhat wrinkly, sometimes with a few scattered very short projections. Light yellowish brown; the outer shell is thin, but firm. Internally it is of a soft, uniform porous or spongy consistency, filling the entire gall. The larval cell is rounded and is embedded in the soft internal substance. Diameter 35 to 70 mm.

  Habitat: Summit of Sierra Madre, Chihuahua and Guadalajara, Jalisco, Mexico

  The largest known species of gall-fly and "oak apple gall." 


description:
  A small, short-hairy, round pink cup gall with a smooth rim. Similar to Russo's ["Andricus scutella"](https://www.gallformers.org/gall/3128) on Quercus oblongifolia. Observed in January in Guanajuato.


externallink: https://www.biodiversitylibrary.org/item/84975#page/12/mode/1up
description:
  Amphibolips nigra, sp. nov.

  [only a female described]

  Habitat: Durango, Mexico. February 1-7, 1897 (Dr. Edward Palmer). 


externallink: https://www.biodiversitylibrary.org/item/84975#page/11/mode/1up
description:
  Dryocosmus favus sp. nov.

  Gall. — In clusters from about fifty to one hundred on the trunks of young red and scarlet oaks (Quercus rubra and coccinea), immediately above the ground, in autumn. Hard and woody (when dry) probably soft when fresh, monothalamous. Oblong, narrower at base than at apex, which is flat. In form they are somewhat like square tubes or five or six-cornered tubes, giving them the appearance of cells of a honeycomb. Hollow inside and rather thin-walled. The fly emerges from the apex of the gall. Length, 5 mm. ; width of apex, 3 mm. ; diameter of cluster, 28 mm. 

  Habitat: Phillips Bluff, La.; Fleetwood, Pa. 

  The fly was described from many specimens loaned to me by Prof. A. D. Hopkins. The species belongs to the European genus Dryocosmus Giraud not heretofore recorded from North America. The fly emerges very early in spring and the gall reaches maturity late in fall. 


externallink: https://www.biodiversitylibrary.org/item/32322#page/94/mode/1up
description:
  Amphibolips palmeri, n. sp.

  Two or three years ago I received from Mr. B. Pickman Mann a very large oak apple gall which he had received from Dr. Edward Palmer. It was written upon as follows: "Summit of Sierra Madre, Chihuahua, Mexico. Winter 1885-86, Dr. Edward Palmer." 

  It was the largest oak apple gall I had ever seen, and I kept it very carefully, hoping to rear an insect from it, but none appeared. 

  On this New Year's morning, 1890, I ventured to cut open the precious gall, and was rewarded by finding in it the largest gall-fly I have ever seen. The fly had eaten its way out of the larval cell, and to the outside shell, but becoming discouraged, it had backed its way into the cell again and died. In forcing itself back one of its wings had been turned towards the head and so remained. 

  It gives me very great pleasure to dedicate this remarkable species to the discoverer. Dr. Edward Palmer. 

  Gall. — This immense monothalamous gall is of a light yellowish brown color, round, and measuring two and three-fourths inches in diameter. The slightly uneven surface is polished and shining; the shell is thin, but firm, and the interior of a soft, uniform, spongy consistence throughout. The color is yellowish brown to almost white at the centre ; the larval cell is oval, and measures three- eighths by five-sixteenths in diameter, and is one-sixteenth of an inch thick. The spongy substance immediately surrounding it is no more dense than in other parts.


externallink: https://www.biodiversitylibrary.org/item/36243#page/180/mode/1up
description:
  Callirhytis furnessae, new species

  Late in December, 1911, Mrs. Dwight Furness, of Guadalajara, Mexico, sent me some white woolly galls tinged with pink on oak twigs and resembling those of Callirhytis seminator Harris. They came from Tarecuato, in the State of Michoacan. One of these galls is represented in figure A. A distinctly marked black and white species of Synergus began to issue January 5, 1912, and continued until after February 1. 

  On April 7, 1912, 1 received from Mrs. Furness another box of similar galls but so much larger that I at first thought they must be a different species. These were almost pure white. See figure B. They are probably full-grown specimens of the same species, and from these a Callirhytis began to issue April 20 and continued to emerge until May 20, 1912, coming out in greatest numbers the last week in April. On June 1, 1912, more of the same species of Synergus mentioned above began to emerge, males and females, coming out at intervals until late in December, 1912. Both species are probably new. 

  Host : An unknown species of oak, probably of the white oak group [Quercus rugosa added as a placeholder], and the one common to high altitudes on the western slope of the central plateau of Mexico. 

  Gall : Large woolly mass nearly or quite encircling twigs 5 mm. or less in diameter. When full grown the largest specimen measured 85 mm. long by 60 mm. in diameter. Each mass is made up of separate elements, from a few to over 1 50 in number, each of which contains a single larval cavity and each of which is covered with a dense coating of long white wool as in C. seminator. But the elements of this gall are quite different from those, being rhomboidal in outline instead of round spindle- shaped, variously distorted by pressure so that no two are alike ; they are not prolonged at apex into a long slender spine which bears the hairs as in seminator but these are hairy to the base; the wall is more woody and thicker instead of a mere shell. See figures C and D.

  This is probably the same gall collected by Silvestri at Jalapa, Mexico, in 1 908 and described by Trotter under the name "? Callirhytis sp." in Boll. Laboro. Zool. Portici 5:127, Tav. I, figs. 7-8, 1910 ; Marcellia 10:55, Tav. I, figs. 7-8. 1911. 


description:
  Ribes inerme added tentatively as a host based on [this unconfirmed observation](https://www.inaturalist.org/observations/88602407). 


externallink: https://www.biodiversitylibrary.org/item/43955#page/125/mode/1up
description:
  Holcaspis mexicana, sp. nov.

  Gall. In a compact mass around the terminal twig of a species of oak. More or less rounded with the sides usually flattened and pressed out of shape. Smooth, somewhat shining, clay brown more or less tinged with red. Hard and woody with a single rounded larval chamber near the base of the gall and firmly imbedded in the hard inner substance. The individual galls measure from 8-18 mm. in diameter and the entire mass 30 mm. in length and 25 mm., in width. 

  Habitat: Guadalajara, Mexico. (D. L. Crawford.) The specimen I received from Prof. C. F. Baker.


description:
  Disholcaspis laetae, n. sp.
  Agamic form

  Gall: Basically but not closely similar to that of [D perniciosa.](https://www.gallformers.org/gall/942) Quite globular in shape, with a drawn-out, nipple-shaped tip; color light tan yellow to rose and tan brown, weathering darker; the surface smooth and shining, entirely without scurf; up to 9 mm in diameter; occurring as scattered galls on stems, or in small, compact clusters of usually 3 to 5 galls.

  Host: Quercus laeta

  Range: San Luis Potosi: Rio Verde. Probably restricted to a portion of the Eastern Sierra which includes the eastern mountains of San Luis Potosi.

  Life history: Adults Feb 15

  This species is a member of the same complex as the American species Disholcaspis perniciosa. It is a very close relative of D potosina which is described below. Laetae and potosina occur together in the Eastern Sierra of San Luis Potosi; but laetae occurs on the small tree, Q laeta, and D potosina occurs on scrub oaks of the Q potosina group. The galls of laetae are globular to breast-shaped, and they occur only as scattered galls or in compact clusters of 3 to 5 galls; the galls of potosina are more ellipsoidal or compressed cushion-shaped, and they occur in clusters of 12 to 20 galls continuously distributed along the stem.

  Laetae is still closer to D purlans which occurs in the not distant Sierra of northern Hidalgo. The galls of the two are very nearly alike.


description:
  Disholcaspis potosina n. sp.
  Agamic form

  Gall. Similar to that of [D. perniciosa](https://www.gallformers.org/gall/942). Ellipsoidal or compressed cushion-shaped, without a nipple-like tip; color rich tan to ruddy brown, darkening to brownish black with age; the surface fairly rough, with a bit of puberulence on fresh galls, with some rough scurf on weathered galls; up to 8. num, in length and 5.mm. in height; occurring in fair-sized clusters of up to 20 galls continuously distributed along the young stems. 

  Host. Quercus potosina variety, the common scrub oak of the area, 

  Range. San Luis Potosi: Rio Verde, 14 W, 6500’. Cerritos, 25 W, 6000’. Probably restricted to a portion of the Eastern Sierra of Mexico including the eastern mountains of San Luis Potosi. 


description:
  Disholcaspis pulla, n. sp. 
  Agamic form

  Gall. — Basically but not closely similar to that of [D. perniciosa.](https://www.gallformers.org/gall/942) Pointed breast-shaped, the swollen, globose base terminating in a conical tip, with a fairly fine point; color tan brown, weathering darker brown: with a heavy tan scurf (as heavy as in the D. cinerosa complex); up to 7.5 mm. in diameter and 9.0 mm. high; occurring in dense, elongate clusters of up to 20 galls, spreading for 40, or 50. mm. along the young twigs. 

  Host, — A tree form of Quercus breviloba [sinuata breviloba]. 

  Range. — Nuevo Leon: Monterrey, 28 SE, 1300’. — Tamaulipas: Villagran, 5 S, 1000k — Probably confined to the single oak in the northeastern corner of Mexico, at low elevations east of the Eastern Sierra.

  Life History. — Adults: November 29. December 6. 7, 14. The bulk of the emergence late in November. 

  This species in common on the big oak of the Q. breviloba complex which occurs at places along the Laredo-Mexico City highway between Monterrey and Ciudad Victoria. This puts it 150 miles south of the Rio Grande. There is no direct connection with eastern Texas but, there is a more round-about connection with Central Texas, and a fairly direct connection through Coahuila with the mountains of the Big Bend of Texas. Also in Coahuila, eastern and Western Sierras meet; and it is, in consequence not surprising to find the present species of cynipid a close relative of the Rocky Mountain D. perniciosa and of the other Rocky Mountain and Western Sierran species of the complex. The species is not so closely related to any of the other members of the complex described in the present paper.


description:
  Disholcaspis purlans, n. sp.
  Agamic form

  Gall. — Basically but not closely similar to that of D. perniciosa. Swollen breast-shaped, the irregularly globose base terminating in a bluntly conical tip but not in a fine point; color tan or rosy brown, darkening with age; smooth and shining, entirely without scurf; up to 10. mm. in diameter and IL mm. high; occurring singly or in small, compact dusters of 2 to 4 galls. 

  Host. — A small tree of the Quercus reticulata complex. Range. — Hidalgo: Jacala, 7 NE, 5000'*. Jacala, 5 W, 5000’. — Probably restricted to a portion of the Eastern Sierra of Mexico in northern Hidalgo and in the immediately adjacent areas of other states. 

  Life History. — Adults: December 10. January 2, 16. Most of the emergence in the first half of December. 

  This insect occurs on one of the small trees of the Q, reticulata group of oaks in the northern end of the state of Hidalgo. In the same area, D. purpurea occurs on the low dwarf oaks; but purpurea has black on and between the anterior parallel lines and on the lateral lines, and it is not a very close relative of purlans, purlans is more closely related to D. laetae from the Eastern Sierra of San Luis Potosi. The galls of purlans and laetae are very similar. 


description:
  Disholcaspis purpurea n. sp. 
  Agamic form

  Gall. — Basically similar to that of [D. perniciosa](https://www.gallformers.org/gall/942). Ellipsoidal or swollen (less often compressed), cushion-shaped, usually without a nipple-like tip though sometimes with a blunt tip; color yellow brown to tan, rose brown, and darker brown, darkening with age; essentially smooth and shining, without bloom or scurf; up to 8. mm. in length and 7. mm. high; occurring in dense, elongate clusters of up to 30 galls spread for 40. mm. or more along the stems. 

  Host. — Quereus repanda var. [unclear if this is Quercus repanda or Quercus microphylla today], the low, dwarf oak of the region. Range. — Hidalgo: Jacala, 24 SW, 680J’, — Jacala, 7 NE, 5000’. — Probably restricted to the repanda group of dwarf oaks in a portion of the Eastern Sierra of Mexico which includes the northern end of the state of Hidalgo. 

  Life History. — Adults: December 1, 4, 10, 11, 14. January 1, 8, 24. Most of the emergence near the middle of December. 

  This insect, from the very low dwarf oaks of northern Hidalgo, belongs to the perniciosa-potosina-pulla lines of species in the perniciosa complex. The geographically closest species is potosina. The galls of purpurea are somewhat larger than those of potosina, and distinctly swollen cushion-shaped — not laterally compressed as in potosina. 


description:
  Disholcaspis regina, n. sp.
  Agamic form

  Gall. — Basically but not closely similar to that of [D. perniciosa](https://www.gallformers.org/gall/942). More or less globose, vertically elongate and laterally compressed, often resembling grains of dent corn in shape, with a swollen and well-rounded top without a distinct tip, or with a tip barely indicated; rose-purple in color, yellow tan on the compressed surfaces which are unexposed to light; -entirely smooth and shining, without bloom or scurf; tip to 13. mm. in height and 8. mm. in diameter; occurring in dense dusters of up to 15 galls packed along the stems. 

  Host, — Quercus macrophylla [magnoliifolia], the largest-leaved white oak of the area. 

  Range. — Guerrero: Taxco, S NE — Probably restricted to the state of Guerrero, or to a portion of that state, in southwestern Mexico, 

  Life History, — Adults: January 20. 

  This insect, Disholcaspu regina, from an eastern locality in the state of Guerrero, is an extreme development in the perniciosa complex. The galls are unlike anything else in the complex, distinctly suggesting an elongate grain of dent corn. All of these characters are approached by the more northern species in the evolutionary line which leads to regina but regina is the most extreme development yet described in the group.


description:
  Bicolored growth from Fallugia paradoxia flower. About two times the height of normal dry flower. Found in New Mexico in January.


description:
  Dros moreliense, n. sp. 
  Agamic form

  Gall. — The cylindrical basal stalk rather slender, up to 2.5 mm. in diameter, short, expanding gradually into the cupped body of the gall; without an expanded, saucer-like base to the stalk; the upper edges of the gall rather thick; color dull brownish red; up to 6.5 mm. in diameter and 7. mm. high. 

  Host. — Quercus conglomerata [rugosa], Q. texcocana [deserticola]. 

  Range. — Michoacan: Morelia, 14 E, 7000’ (Q. conglomerata), — Mexico: Mexico City, 12 W, 8500’ (Q. texcocana). — Probably widespread on all but the dwarf oaks in the states of Mexico and Michoacan. 

  Life History. — Adults in «spring» and April 10. 

  The gall is unique in the complex in lacking the flared or saucer-like base which, in all the other species, connects the stalk of the gall with the leaf. The species is therefore more readily recognizable than some of the others in the group. 

  Although the recorded localities (east of Morelia and west of Mexico City) are 120 miles apart, and although the hosts of the two collections are different (Q. conglomerate and Q, texcocana), we have other species of cynipids which show similar distributions and host relations. 

  Dros periscele, n. sp. 
  Agamic form

  Gall. — The same as the galls of C. picatum and C. repicatum. Basal stalk tapered to a narrow point less than 2.0 mm. in. diameter, the cupped body of the gall expanding gradually from the stalk, the base somewhat wider than the. stalk, thin, plate-like; the upper edges of the gall about 1.7 mm. in width; color bright ox-blood to deep brownish red; up to 10. mm. in diameter and 11. mm. high. 

  Host. — Quereus macrophyIla [magnoliifolia]. 

  Range. — San Luis Potosi: Rio Verde. 14 W, 6500’. Possibly restricted to a portion of the Eastern Sierra including the eastern mountains of San Luis Potosi. 

  This species, from the eastern mountains of San Luis Potosi, is very close to D. repicatum the range of which centers in Guanajuato. The two occur on the same host, Q. macrophylla. 


description:
  Dros perlentum, n. sp. 
  Agamic form

  Gall. — The same as the galls of petasum. Basal stalk uniformly cylindric, slender, averaging 2.7 mm. in diameter; the cupped body of the gall expanding abruptly from the stalk; the base somewhat wider than the stalk, thin, plate-like; the upper edges of the gall broad, about 2. mm. in width; color yellowish-brown and red: up to 10. mm. in diameter and 8. mm. high. 

  Host. — Quercus macrophylla [magnoliifolia]. 

  Range. — Jalisco; a locality 35 E of Aguascalientes, 7000’. — Probably restricted to northernmost Jalisco.

  Life History. — Adults: April 15. This and D. petasum are the only described Mexican species with yellow-brown galls which have distinctly broadened, inrolled edges on the cup which is terminal on the body of the gall. The ranges of the two species are contiguous, the present species having been collected in the northeastern corner of the state Jalisco, in the narrow extension which lies between Aguascalientes and Guanajuato. Petasum occurs in more southern and western Jalisco. Both perlentum and petasum occur on Q, macrophylla. 

  Dros petasum, n. sp. 
  Agamic form

  Gall. — The same as the gall of perlentum. Basal stalk uniformly cylindric, slender, averaging 2.7 mm. in diameter; the cupped body of the gall, expanding abruptly from the stalk; the base somewhat wider than the stalk, thin, plate-like; the upper edges of the gall broad, about 2, mm. in width; color yellow-brown and red; up to 9. mm. in diameter and 11, mm. high.

  Host. — Quercus macrophylla

  Range. — Jalisco: Guadalajara, 10 W, 6000 k Magdalena, 4 N, 4300' (galls). — Probably restricted to the central and southern portions of the state of Jalisco. 

  Life History. — Adults: March 3, 10, April 1, Most of the emergence in the first half of March. Petasum and perlatum are the only Mexican species of the complex with yellow-brown galls which have broad, inrolled, upper margins. Petasum has been recovered from Jalisco west of Guadalajara; perlentum was found in the northeastern corner of that state near Aguascalientes. 


description:
  Dros picatum, n. sp.  
  Agamic form

  Gall. — The same as the galls of periscele and repicaturn. Basal stalk tapered to a narrow point less than 2.0 mm. in diameter; the cupped body of the gall expanding gradually from the stalk; the base somewhat wider than the stalk, thin, plate-like; the upper edges of the gall about 1.7 mm. in width; color bright ox-blood to deep brownish red; up to Q mm, in diameter and 10. mm. high. 

  Host. — Quercus macrophylla, 

  Range, — Guanajuato: San. Felipe, 20 SW, 8000L Zacatecas: La Mesa, 7000’. — Probably confined to Q. macrophylla, but widespread wherever that oak occurs in Central Mexico, possibly from Zacatecas to Queretaro. 

  Life History, — Galls fresh, very sticky, December 7. Adults: December II. March 20. April 20, 25. Most of the emergence late in April, 

  There are two species of this complex represented in our collections from Guanajuato, and even from the one locality 20 miles southwest of San Felipe. These two species, picatum and repicatum are obviously host isolates, picadum being restricted to Q. macrophylla while repicatum is known from most of the other oaks of the region (L e. from the dwarfs, Q. jaralensis and Q, microphylla, and from the aborescent species, Q, sacame and Q. undaia). 

  Dros repicatum, n. sp.
  Agamic form

  Gall. — The same as the galls of periscele and picatum. Basal stalk tapered to a narrow point less than 2.0 mm. in diameter, the cupped body of the gall expanding gradually from the stalk, the base somewhat wider than the stalk, thin, plate-like; the upper edges of the gall about 1.7 mm in width; color bright ox-blood to deep brownish red; up to 7.5 mm. in diameter and 8.0 mm. high. 

  Host. — Quercus jaralensis, Q. mlcrophylla, Q. sacame, Q. undata. Not found on Q. macrophylla. 

  Range. — Aguascalientes: Pabellon, 20 W, 7000’, (Q. undata; also galls on Q. sacame). Zacatecas: La Mesa, 7000’ (Q. sacame). Guanajuato: San Felipe, 20 SW, 8000’ (Q. jaralensis). Leon, 20 NE, 9000’ (Q. jaralensis, Q. mierophylla). Probably found on all the white oaks except Q. macrophylla, throughout a wide area in Central Mexico, at least from Zacatecas to Queretaro.

  Life History. — Adults: December 14. March 20, 30. April 10. May 10. Most of the emergence late in March and early in April. 

  The present complex is represented on Q, macrophylla in the state of Guanajuato by the species picatum. Dros repicatum is a host isolate occurring in the same area on most of the oaks other than Q. macrophylla) ie. on the dwarf oaks, Q. jaralensis and Q. microphylla, and the taller trees, Q, sacame and Q. undata. Although repicatum and picatum are host isolates in the same area in Guanajuato, repicatum is really closer to D. periscele from the eastern part of San Luis Potosi. 


description:
  Dros moreliense, comb. rest (=D periscele, n. syn.)

  [Photos of this gall appear on page 6 of the pdf]

  Basal stem conical, cup-shaped body expanding gradually from the stem; the upper edges of the gall are thin, which means that the gall does not retain a circular outline on the top; color varies between red and brown. 

  Galls small (up to 5.6 mm in diameter and 7 mm in height), sometimes very conical


description:
  Dros perlentum, comb. rest. (=D petasum, syn nov)

  [Photos of this gall appear on page 6 of the pdf]

  Basal stem uniformly cylindrical, cup-shaped body abruptly expanding from the stem; the upper edges of the gall are thick, which causes a circular border to persist; yellowish-brown or reddish color.


description:
  Dros picatum, comb. rest. (=D repicatum, n. syn.)

  [Photos of this gall appear on page 6 of the pdf]

  Basal stem conical, cup-shaped body expanding gradually from the stem; the upper edges of the gall are thin, which means that the gall does not retain a circular outline on the top; color varies between red and brown.

  Galls large (up to 10 mm in diameter and 11 mm in height), never strongly conical 


description:
  The taxonomic position of the Dros species north of Mexico is discussed, concluding than at least two species belong to the genus Dros: D. sessile (Weld, 1927) and D. viscidum (Weld, 1944).


description:
  Druon linaria, n. sp. 
  Agamic form

  Gall. — Wool covering creamy white, yellowing a bit with age; the individual hairs fairly straight, not long but closely compact clusters closely in diameter and mm. in length, and completely covering the larval cells; all compact, circular in outline, up to 9. mm. 5. mm. high. The larval cells averaging 3.0 rather slender, averaging only 3 or fewer.

  Host. — Quercus oleoides, a member of die Q. virginiana group of evergreen white oaks. 

  Range. — Tamaulipas: Ciudad Victoria, 21 W, 3200L —- Probably confined to the single host in a Eastern Sierra of Mexico. 

  Life History. — Adults: February 10, 25. March 10. 

  The oak host of this species, Quercus oleoides, is a close relative of Q. virginiana of the United States. The gall is distinct from all others here described in being creamy white, small, rounded masses containing only two or three larval cells in the type locality of linaria, Druon malinum occurs on the broader leaved evergreen oak. Q, polymorpha. 


description:
  Druon protagion, n. sp.
  Agamic form

  Gall. — Wool covering brownish yellow, russet, or (most often) bright purplish brown, dark with age, the individual hairs rather short but densely matted, closely compact, usually covering the individual larval cells, although the tips of the cells are sometimes exposed; single clusters circular, closely compact, averaging near 10. mm. in diameter and 8. mm. high, but agglomerate clusters oval or more elongate and up to 30. mm. in length. The larval cells rather stout but elongate, averaging about 3.0 mm. in length; usually with 3 or 4 cells in individual clusters, with more in agglomerate clusters. 

  Host. — Quereus conglomerata [rugosa], an oak with rather large, smooth, and entire leaves. 

  Range. — Michoacan: Morelia, 14 E, 7000’. — Posssibly extending from Morelos to Jalisco on Q. conglomerata and its close relatives.

  Life History. — Adults: March 25. April 2, 20. Most of the emergence in the last week of March and first week of April. 

  From the other species described in this present paper, protagion is distinct in having a rather small gall which is wine purple or purple brown in color. 

  Druon polymorphae, n. sp.
  Agamic form

  Gall. — Wool covering light gray tan to buff brown, rarely touched red purple; the individual hairs quite long, wavy, forming a tangled, rather compact mass which ordinarily covers the larval cells, though the cells may be exposed in smaller or worn dusters; typical clusters rounded, compact, averaging near IF mm. in diameter and S. mm. high, with agglomerate masses more elongate, up to 32. mm. in length. Larval cells averaging 3.5 nun. in length, rather slender, averaging 3 to 7 in a duster.

  Host. — Quercus polymorpha, the large tree bearing entire, smooth, evergreen leaves.

  Range. — San Luis Potosi: Cerritos, 25 W, 6000L Probably confined to a portion of the Eastern Sierra centering in the eastern part of the state of San Luis Potosi.

  Life History. — Adults: February 29. April 10, 16, 23. Most of the emergence near the middle of April.

  This species, polymorphae, from a locality in the Sierra of the eastern part of San Luis Potosi occurs on the same oak as D. mailnum The latter species is found further northeast in the Sierra of southwestern Tamaulipas. The two species on Q, polymorpha are not as close relatives as the two species found in the one locality in Tamaulipas. The gall resembles that of malinum in being tan to brown of considerable size.

  Druon malinum, n. sp.
  Agamic form

  Gall. — Wool covering buff or tan brawn, the individual hairs quite tangled, rather long, moderately although not closely compact, but completely hiding the larval cells; the irregular masses up to 40. mm. in length and 9. mm, in height, but compact, oval masses averaging near 12. mm. in diameter and 6. mm. high. The larval cells averaging 3. mm. in length, moderately stout and long, averaging 3 to b in a cluster, though many more may occur in elongate, conglomerate masses.

  Host. — Quercus polymorpha, the tallest, broad-leaved oak of the region.

  Range. — Tamaulipas: Ciudad Victoria, 21 W, 3200’. — Probably confined to this oak (and its relatives?) in a portion of the Eastern Sierra of Mexico.

  Life History. — Adults: March 15.

  This species, malinum, occurs on the broader-leaved, evergreen oak of the region, namely Q. polymorpha. In the same area, Druon linaria occurs on Q. oleoides. The gall of malinum is very distinct from the gall of linaria in being a buff or tan brown, woolly mass of considerable size.


description:
  Druon receptum, n. sp.
  Agamic form

  Gall. — Wool covering grayish yellow-brown, darkening with age; the individual hairs very long, considerably tangled, completely hiding the larval cells: the individual clusters rounded to oval, dense but fluffy, averaging near 20. mm. in diameter and 12. mm. in height, but commonly with several clusters in large, elongate masses up to 35. mm. in length. The individual larval cells averaging over 3.5 mm. in length, rather robustly elongate, averaging only 4 to 8 in a single cluster. 

  Host. — Quercus rhodophlebia [rugosa], an oak with large and russet-hairy leaves. 

  Range. — Mexico: Mexico City, 20 S, 9200'. — Probably confined to the mountains rimming the Valley of Mexico, unless extending to the southeast toward Vera Cruz.

  Life History. — Adults: March 20, 22, 29, April 1. May 3. 

  Receptum has a distinctive gall which is light grayish brown in color, fluffy with its long and tangled hairs, and conspicuous because of its large size and often agglomerate massing on the leaves of this oak, Q. rhodophlebia, in the mountains near Mexico City.


description:
  Druon rusticum, n. sp.
  Agamic form

  Gall. — Wool covering cream white to tan and russet brown, the colors often mixed in single dusters; the individual hairs not long, quite straight, hardly covering the larval cells and obviously tufted about each individual cell; making continuous but very irregular, narrowly elongate masses up to 25. mm., averaging nearer 13. mm. in length. The larval cells averaging only 1.5 mm. in length, elongate but less so than usual in the complex, averaging 4 to 10 in a cluster. 

  Host. — Quercus macrophylla, the largest-leaved oak of the Mexican Cordillera. 

  Range. — Guerrero: Taxco, 8 NE, 8000k •— Chilpancingo, 6 S, 4000^ — Probably confined to the state of Guerrero in southwestern Mexico. 

  Life History. — Adults: April 6, 10, 15. May 1. 

  This insect from Guerrero may occur over a goodly portion of that southwestern states in Mexico. The galls of [rusticum and protagion] are distinct, that of rusticum being mostly tan and russet, with short tufts of fairly straight hairs which make obviously irregular rows along the leaf veins — the galls of protagion being compact and rounded masses of wine purple or purple-brown wool. The parallel development of black, in rusticum and in the Mendelian race of protagion is an instance of similar mutations being involved, in one case in development of a Mendelian race in the midst of the parental species, and in the other case in the formation of a pure population which is a distinct species.


description:
  Femuros repandae, n. sp.
  Agamic form

  Gall. — As described for the genus. Possibly averaging smaller than the gall of ruidum; up to 17. mm,, averaging nearer 14. mm. in diameter. 

  [Description for the genus: Large, globular, monothalamous bud galls. Galls quite regularly spherical, distorted chiefly by the bracts, deformed leaves, and deformed (broadened) petioles which are closely fused on the surfaces; up to 23, averaging near 15. mm. in diameter; the surface of the gall similar to the bark covering young twigs, touched with red when young, becoming silvery and purple brown with age. Internally more or less solid, with a compact but soft tissue filling the outer third or half of the gall, this giving way to a more spongy and open tissue which supports the larval cell; larval cell central, inseparable, thick- and hard-walled, up to 7.0 mm, in diameter even in rather small galls. Galls terminal on main or side twigs, abruptly rising from the twigs, sessile but not more solidly attached than a normal bud; usually showing normal bud scales at base, occasionally with a deformed or small leaf or even a rare stem developing from the aborted structures on the surfaces of the galls; occurring singly or (rarely) in clusters of two or three galls.]

  Host. — Quercus repanda [Quercus rugosa?], the lowest dwarf among the high mountain oaks in this area. 

  Range. — Mexico: Mexico City, 32 E, 10.600’ (types). — Hidalgo: Pachuca, 7 N, 8700’. — Probably restricted to dwarf oaks of the repanda group in the mountains of Mexico (state), and perhaps through Morelia. 

  Life History. — Adults: April 16, 24 

  This insect occurs on the dwarf oaks of the repanda, group in the high mountains rimming the Valley of Mexico. On the other oaks of the same area, F. ruidum represents the same complex of insects. 


description:
  Femuros ruidum, n. sp.
  Agamic form

  Gall. — As described for the genus. Not distinct from the gall of repandae unless in its larger size; up to 23. mm,, averaging nearer 15. mm. in diameter. 

  [Description for the genus: Large, globular, monothalamous bud galls. Galls quite regularly spherical, distorted chiefly by the bracts, deformed leaves, and deformed (broadened) petioles which are closely fused on the surfaces; up to 23, averaging near 15. mm. in diameter; the surface of the gall similar to the bark covering young twigs, touched with red when young, becoming silvery and purple brown with age. Internally more or less solid, with a compact but soft tissue filling the outer third or half of the gall, this giving way to a more spongy and open tissue which supports the larval cell; larval cell central, inseparable, thick- and hard-walled, up to 7.0 mm, in diameter even in rather small galls. Galls terminal on main or side twigs, abruptly rising from the twigs, sessile but not more solidly attached than a normal bud; usually showing normal bud scales at base, occasionally with a deformed or small leaf or even a rare stem developing from the aborted structures on the surfaces of the galls; occurring singly or (rarely) in clusters of two or three galls.]

  Hosts. — Quereus texcocana [deserticola], Q, conglomerata Q, rhodophlebia [rugosa]. Apparently on all the white oaks of the area except the low dwarfs of the repanda group. 

  Range. — Mexico: Mexico City, 20 S? 4200‘ (Q. rhodophlebia ). .Mexico City, 17 S, 8200’ (Q, conglomerata , Q. texcocana. Mexico City, 12 W, 8500’ (Q. texcocana). — .Morelos: Cuernavaca, 8 N, 8700’ (Q. texcocana, types; also on Q, conglomerata ). — Apparently one species both in the Valley of Mexico and in Morelos, possibly extending further west toward Michoacan and south east toward Vera Cruz. 

  Life History. — Adults: March 5, 15, 20, 29. April 5, 10. 

  In several groups of cynipids we find that the species occurring on the inner faces of the mountains rimming the Valley of Mexico do not extend over the high passes onto the southwest slopes which drop into the valleys of Morelos. In the present Instance, however, it seems to be one species, ruidum which we found on the several oaks in localities south and west of Mexico City, and in the montnins above Cuernavaca In Morelos. Having crossed the high divides at this point, the species may extend some hundreds of miles to the west into Michoacan and, southeastwardly, toward Vera Cruz. 


description:
  Feron tibiale, n. sp.
  Agamic form

  Gall. — Individual galls swollen cylindric, flaring at the broadened tip, covered with more or less crystalline processes, with a few broad filaments (chiefly at the base of each gall), with almost all of the fibers fine, hair-like. The whole forming a more or less solid and tangled mass up to 27. mm. in diameter and 13. mm. high. Purple rose and light brown when voting, becoming light straw brown to russet, rosy brown, or dark brown with age. 

  Host. — Quercus texcocana. [deserticola]

  Range. — Mexico: Mexico City, 25 E, 7000’ (types). .Mexico City, 12 W, 8500’ (galls). — Puebla: El Seco, 5 S\XZ, Extending from the Valley of Mexico southeast toward the state of Vera Cruz. 

  Life History. — Adults: December 5, 16. 23. January 10. February 25. March 2, 9, 10, 15. April 1, 10, 17. Most of the emergence in January and February. 

  This is the southernmost species yet known in the complex with 13-segmented antennae. Tibiale Is closely related to tecturnarum, which is the next species to the north and the most widespread species in Mexico. 


description:
  Feron verutum, n. sp.
  Agamic form

  Gall. — Individual galls long and slender, uniformly cylindrical or flaring at the top, fairly well covered with distinctly crystalline processes all of which are broad and blunt, filamentous, none of which are fine or hair-like. The whole forming a spiny mass in which the individual galls are quite prominent, the clusters up to 55, mm. in diameter and 17. mm. high. Bright purple rose and straw color when fresh, darkening with age. 

  Host. — Quercas macrophylla. [magnoliifolia]

  Range. — San Luis Potosi; Rio Verde, 14 W, 6500b Guanajuato: San Felipe, 20 SW, 8000’. — Spread over an area in Central Mexico, at least from Guanajuato to eastern San Luis Potosi. 

  Life History. -- Adults: April 22, 30. May 1’2. Most of the emergence in the last week of April. 

  This is one of the series which has crystalline, filament-covered galls and insects with 13-segmented antennae. The spectacular gall of the species Is the largest of the complex. The two points from which we have the insects are only about 80 miles apart, but they are separated by broad deserts and barren, mountain areas, and the species probably spreads indirectly through connecting ranges which may involve a goodly portion of Central Mexico. The nearest known relatives are vitreum and validum, from the Valley of Mexico and from Morelos, respectively. These other species are located about 180 miles from verutum. Undescnbed species of the series may occur in the intervening territory. The present species is distinct from validum in having the mesonotum practically naked, and smooth and shining posteriorly; and from vitreum in being darker, with 3 or 4 more of the antennal segments dark brown, and the scutellum more rugose with a well-indicated median groove. 

  Near San Felipe, in the state of Guanajuato, verutum occurs on Q. macrophylla, and testurnarum (of the series with 13-segmented antennae) occurs on Q. chihuahuensisy Q. undata, Q. jaralensis, and possibly other dwarf and arborescent oaks


description:
  Feron vitreum, n. sp.
  Agamic form

  Gall. — Individual galls long and slender, uniformly cylindrical or flaring at the top, more or less covered with distinctly crystalline processes all of which arc broad and blunt, filamentous, not fine nor hair-like. The whole duster forming a spiny mass in which the individual galls are still prominent, the clusters up to 35. mm. in diameter and 12. mm. high. Bright purple rose and straw color when fresh, darkening with age.

  host. — Quercias rhodopidebia (and Q. texcocana?). 

  Range. — Mexico: Mexico City, 20 S, 9200’ (Q. rhodophlebia). Mexico City, 17 S, 8200’ (Q, texcocana?), — Hidalgo: Pachuca, 7 N, 8700- (galls; Q. rhodophlebia). — PossibH extending southeast from the Valley of Mexico on Q. rhodophlebia or its relative, Q. decipiens. 

  Life History. — Adults: March 10.

  This is another of the series of species with 14-segmented antennae and galls which are clearly crystalline with broadened filaments (not tangled, hairs) as a covering. The known localities He north and south of Mexico City on the inner rim of the mountains which bound the Valley of Mexico. Twenty miles south of Mexico City, vitreum was found high up near the limit to which white oak extends. It is only 5 or 6 miles across the divide the the locality (Cuernavaca, 8 N) from which we recovered 2*'. validwn; but the two species are separated by a 10,220 foot pass to which white oak do not extend. The 13-segmented series of the complex is represented by F. tibiale on Q. texeaccma to the east of Mexico City; and the one lot of what is certainly vitreum “from Q. texcocana" from 17 miles south of Mexico City may represent a mis-determination of the host. 

  Feron validum, n. sp.
  Agamic form

  Gall. — Individual galls long and slender, uniformly cylmdiic or flaring at the top, more or less covered with distinctly crystalline processes all of which are broad and blunt, filamentous, not fine nor hairlike. The whole cluster forming a spiny mass in which the individual galls are still prominent, the clusters up to 30, mm. in diameter and 12, mm. high. Bright purple rose and straw color when fresh, darkening with age. 

  Host. — Quercus texcocana. [deserticola]

  Range. — Morelos: Cuernavaca, 8 N, 8700k — Replaced in the Valley of Mexico by F. vitreum, but possibly extending from Morelos to southern Jalisco

  Life History. — Galls: Still fresh January 7. — Adults: April 10. 

  The known material is too scant to warrant generalizations as to usual date of emergence. validum is one of the southern Mexican species with. 13 segmented antennae and distinctly crystalline galls which are covered with broad and blunt filaments instead of the tangle of fine, hair-like processes which characterize the galls of the Mexican species with 13-segmcnted antenae. 

  The nearest relatives of validum are verutum (from Guanajuato to eastern San Luiz Potosi, on Q, microphylla) and vilreum (from south of Mexico City, on Q. rhodophlebia). The galls of all three species are about the same


description:
  Xystoteras cylindratum, n. sp.
  Agamic form

  Gall. —- Small, naked, hollow cylinders scattered on the under surfaces of leaves. Each gall rather regularly cylindrical, a bit swollen below the tip. a bit restricted basally, up to 5.0 mm. in length and 2.5 mm. in diameter, averaging nearer 3.5 mm. in length and 1.7 mm. in diameter. Exterior of gall fairly smooth, entirely naked except for a blue or purplish scurf. Body of gall hollow, open at top, the open cavity penetrating a third or a half of the gall, separated from the larval cell by a thin partition; larval cell floored with a thicker partition beneath which still another cavity is to be found. Young galls straw and light rose oink, sometimes touched more purple red, the whole touched with an ashy-blue scurf; older galls becoming burnt red to purple brown or dark, dirty brown. Each gall separate, but galls often occurring in great numbers and in dense masses, usually on under surfaces, rarely on upper surfaces of leaves of oak, 

  Host. — Quereus texcocana. [deserticola]

  Range. — Mexico: Mexico City, 22 E, 8200\ and 25 E, 7000\ — Puebla: El Seco, 5 SW, S200\ — Apparently extending from the Valle}' of Mexico southeastwardly toward Vera Cruz.

  Life History. —- Adults: December 5, 16, 23. January 9. March 10, 15. April 1, 10. Most of the emergence in the middle of March. 

  This species is very abundant on the oaks directly east of Mexico City. Both in 1931-32 and in 1935-36 we found the insects so abundant that quarts of the tiny galls might have been gathered from small stands of trees — except for the difficulty of picking up such small objects after they had once fallen to the ground. At the present stage of our studies, I do not recognize what are the closest relatives of the species.


description:
  Slight A. canescens leaf blister. Galled leaves yellowed overall with purple tinge farther up the leaf. They are folded tightly down the middle and detach much more easily than healthy leaves. A galled leaf with a large hole in it was pulled open and inside was a chamber with frass inside. Found in New Mexico in January. 


description:
  Andricus tamaulipensis, nom. nov.

  Disholcaspis mexicana
  Holcaspis mexicana

  [A photo of the galls of this species appears on page 3 of the pdf. They do not closely resemble Beutenmuller's figure.]

  [The galls of A tamaulipensis are unmistakable. They are more or less circular, very hard, larval chamber single and eccentric placed closer to the base of the gall and surrounded by a lignified tissue. Beutenmuller (1911) mentions that they form clusters but in Tamaulipas they have been collected only alone or in clusters of 2-3 galls, sometimes fused. Unfortunately the galls that were used for the description of Holcaspis mexicana Beutenmuller have not been found. 

  Finally, the Kinsey specimens mentioned above were collected from oaks in the section Quercus while our specimens have been obtained from galls collected on the section Lobatae. This fact supports even more strongly the possibility that Kinsey's specimens do not correspond to the species mentioned earlier. Quercus rysophylla Weath is the first host known for A tamaulipensis. This finding can't be attributed to a misidentification of the oak since in El Madroño only two species of oak are found: Q rysophylla and Q laurina, both in the section Lobatae. The genus Andricus produces mainly galls on the section Quercus but a small group of species forms them on the section Lobatae, see Pujade-Villar et al (2009) for those species in Mexico. Possibly, the species that produce galls on the section Lobatae are misplaced in Andricus but to be more precise will require additional morphological studies. 


externallink: https://www.biodiversitylibrary.org/item/114064#page/147/mode/1up
description:
  Antron tepicana, new species

  Host: Quercus reticulata [rugosa]

  Gall: Similar to that of A chica, up to 60 mm in diameter, the inner pile with transparent, tapering tips 5 mm deep, the long outer crumpled hairs not swollen at the base. Larval cell up to 12 mm high by 6 mm in diameter.

  Habitat: Galls were collected Jan 22 1936, at Tepic Mexico. Adults emerged and died in box before April.


description:
  Andricus opertus
  Agamic generation

  [Photos of this gall appear on page 4 of the pdf]

  Callirhytis nigra
  Diplolepis operta
  Andricus nigridius
  Andricus opertus

  GALL (Figs. 3, 4). Usually completely concealed within the leaf buds, eccentric, occasionally causing minor distortion. Approximately 2.5 mm long, shape varying from flattened-ovoid to pointed-ellipsoid. The pale brown shell of the mature gall is polished and sparsely striate longitudinally. There is usually only one gall in a bud. It may be distinguished from the somewhat similar gall of Disholcaspis eldoradensis (Beutenmueller) by its earlier occurrence, smaller size and stubbier shape, generally darker color, and more striate appearance. 

  Range: northern CA

  Agamic females chew relatively large circular exit holes subapically on the gall and through the side of the bud during late March to mid-April. They oviposit in the opening leaf buds.


description:
  Disholcaspis eldoradensis
  Bisexual generation, new description

  [Photos of this gall appear on page 4 of the pdf]

  GALL (Fig. 5). Bluntly pointed ellipsoid inside the bud, usually stunting it, and frequently protruding; about 3 mm long, and 1.8 mm wide sub-basally; seldom symmetrical. Very pale brown; the surface with distinct fine longitudinal reticulation. Subapical exit holes are rough-edged, subcircular, sometimes apical. Monothalamous, usually only one gall to a bud; more often in small lateral buds on slow-growing trees than on stout or terminal buds. 

  Agamic females emerge during November and December and oviposit in buds at that time. Most of the gall and larval development occurs early the following spring. Adults of the bisexual generation emerge during April and May, and oviposit in the twig bark.


description:
  Disholcaspis eldoradensis
  Agamic generation

  [Photos of this gall appear on page 4 of the pdf]

  GALL (Fig. 6). On last year's twigs in the intervals between buds, sometimes close together; usually on fast-growing relatively young trees. Galls are oriented along the twig, but seldom evenly or in rows. Number may vary from one to several dozen; relatively small numbers on robust twigs attain greater size and more perfect shape than those in large colonies on small twigs, which may be distorted by crowding; monothalamous. Circular emergence holes are usually at the ends of the galls. The hard broken shells and deep scars may remain on a tree for years; small twigs are often killed by the galls. Frequently the same tree is utilized for the agamic generation year after year, and develops a clipped stunted appearance.

  Range: San Francisco area

  Adults of the bisexual generation emerge during April and May, and oviposit in the twig bark. Gall colonies usually result from one female rather than from communal oviposition. First evidence of a gall is a slight swelling of the bark, which splits longitudinally as the gall develops. Very young galls are yellow, changing to green, brown, and shiny dark red by early autumn; thereafter the color becomes dull and darker. Agamic females emerge during November and December and oviposit in buds at that time. 


description:
  Bassettia ligni
  Agamic generation

  [Photos of this gall appear on page 6 of the pdf]

  GALL (Figs. 9-1 1 ). Monothalamous cells beneath the bark, approximately 1 x3 mm (Fig. 10); single, confluent, or crowded. Crowded galls often small and irregular in form (Fig. 11). Oviposition is usually in twigs at least 2 years old, so galls and emergence holes appear on third-year growth (Fig. 9), but they may be present in 2- to 6-year growth. Single or scattered groups of galls are seldom apparent, but when a twig is heavily attacked it is slightly swollen and growth is adversely affected (Fig. 12). After the insects leave, the cells become dark in color and sometimes contain a staining fungus. Emergence holes may remain visible on the branch for several years. Galls may be on trees of any age, and often seem restricted to an individual tree within a group. 

  Range: northern CA and possibly central OR

  Agamic females emerge from the bark in mid-April; individual "colonies" have an average emergence span of only 5 or 6 days. They prefer calm sunny days with temperatures above 55°F to oviposit in the leaves within the swelling buds. The cream-colored eggs are elongate conic-ovoid, ca. 135X.055 mm. Dissected females contained an average of 320 eggs. The galls of the bisexual generation become visible in about 4 weeks. 


description:
  Bassettia ligni 
  Bisexual generation

  [Photos of this gall appear on page 6 of the pdf]

  GALL (Figs. 7, 8). Inconspicuous blister-like swellings in the blade tissue of mature leaves, seldom near the margins or in the veins. Mature galls are approximately 4 mm diam., but only about 2 mm are visible on the top surface of the leaf as an indistinct subcircular swelling, slightly brown-puckered off-center. Living galls are more noticeable on the underside of the leaf where the swellings are more pronounced, slightly smoother and paler than the surrounding tissue, and with dimpled centers (Fig. 7). Adults normally emerge from the upper surface, leaving rough subcircular exit holes that soon develop elevated margins (Fig. 8). These holes become more conspicuous as the leaves die. Galls may contain 1-4 cells and are frequently confluent; polythalamous galls more often contain males. Individual leaves may have 1-30 galls. 

  Adults of the bisexual generation emerge during late June to mid-July. Males wait on nearby leaves for females to emerge. Adults are most active during mid-day. Females oviposit on 2- to 5-year-old stems, often on their host tree in the areas where the agamic generation emerged earlier in the year. The pupal stage develops by September. 


description:
  Liodora pattersonae
  Agamic generation

  [Photos of this gall appear on page 12 of the pdf]

  GALL (Fig. 15). On the underside of mature leaves, but not on principal veins or extreme margins; on trees of all ages and sizes. Single and monothalamous, usually several to a leaf, but 1-100 possible. Individual galls disc-like, thin, 3-6 mm diam., 51. mm maximum thickness at elevated midsection; finely radially striate. Pale ivory-green, occasionally dappled darker as galls mature to a tan color. Overwintering galls may fall from or with the leaves. 

  Range: west-central CA

  Adults of the bisexual generation emerge during late May to early June, and females oviposit on the undersides of leaves. Galls that are too crowded develop at an uneven rate and many do not mature. The agamic females may emerge the following spring, late March to early April; however, a diapause within the gall for 1 or 2 years is common. 


description:
  Disholcaspis crystalae, n. sp.
  Agamic form

  Gall (Fig. 1c): Globular, spherical, lignified, growing in clusters of two to five galls. Green when young and growing, turning brown when old. Surface provided with a large number of short protuberances reminding the fruit of Arbutus unedo L. or the gall of the agamic form of Cynips quercusfolii; rarely protuberances scarce or almost non-existent. Diameter 8 to 14 mm. Easy to cut, external wall (2mm) is not hard, corky texture. Internally with a large air chamber in which the yellow, oval and friable larval chamber is housed in the lower part. The larval chamber detaches easily, being free in the internal chamber.

  Biology: Only asexual females are known, inducing galls on Quercus laeta Liebm. (Quercus Section Quercus, white oaks), endemic to Mexico (Valencia, 2004; Romero-Rangel et al., 2015). Galls were collected early in end June, and adults emerged in December to January. Further study is needed to determine the phenology of this species.


description:
  D. taumalipensis is transfered here de novo to Disholcaspis genus: D. mexicana (Beutenmüller) (= Andricus taumalipensis Pujade-Villar n. syn.)


description:
  Amphibolips damfi, n. sp. 
  (bisexual form)

  Gall. — A spongy oak apple similar to the American A. confluentus. More or less spherical, thin-shelled the spongy interior dense though soft, the larval cell central or nearer the base of the gall; galls up to 48. mm, in diameter; completely separable, borne on twigs. 

  Host, — Q. ocoteaefolia [laurina]. 

  Range. — Oaxaca: Sierra Juarez between Ixtlan de Juarez and Tepanzacoako, 8700b Probably restricted to a more southern portion of Mexico, centering in Oaxaca, 

  Life History. — Bisexual galls mature at least by February. Bisexual adults emerging at some time between February 24 and April 15. 

  Dampfi is a strikingly distinct insect producing a gall of the spongy oak-apple type. 


description:
  Amphibolips fusus, n. sp.

  Gall. — A slender to globose, spindle-shaped oak apple, - with tip and base quite fine, with greatest diameter near middle of gall, up to 35. mm,, averaging nearer 30. mm. in length, up to 25. mm., averaging nearer 10, mm. in diameter. The outer shell weathering dirty brown or darker in color, probably green, rosy, and straw when fresh; smooth and naked except for minute, raised, black specks and splotches which are fairly abundant over whole gall; internally very dense (hardly spongy), quite solid except for the larval cell; 1 completely separable, borne on twigs. 

  Host. - Quercus eduardi, the shining, prickly-leaved black oak of the area, a close relative of the American Q. Emoryi. 

  Range. — Zacatecas: Cantuna, 6 N, 6700’ (types). Zacatecas, 25 SW. La Mesa, 7000' (gall). Probably restricted to a central portion of the Western Sierra of Mexico, including the state of Zacatecas.

  Life History- — Unknown. All live adults (bisexual or agamic?) were emerged from galls found in November. All of the adults which we have of this species were dead and cut from old galls gathered in November. Whether these were remnants of a spring-emerging, bisexual generation, remnants of a just-emerged, fall, agamic generation — or. indeed, whether there is any alternation of generations at all in these southern species of the genus, it seems impossible to determine on the basis of the scant material now available


description:
  Amphibolips nassa

  Gall. — A rather large, globose but slightly spindle-shaped oak apple with a fine tip and base. Body of gall quite globose, with greatest diameter near middle of gall; up to 40. mm., averaging nearer 24. mm. in length, up to 28. mm., averaging nearer 20, mm. in diameter. Outer shell weathering dirty brown or darker in color, probably green, rosy, and straw when fresh; smooth and naked except for minute, raised, black specks and splotches which are fairly abundant over whole gall; internally very dense (hardly spongy), quite solid except for larval cell; completely separable, borne on twigs. 

  Host. — Quercus serrulata [castanea], the broader-leaved black oak, and Q. mexicana, the narrow- and entire-leaved black oak of the region. 

  Range. — Michoacan: Purepero, 5 W, SW)’ (Q. serrulata, types; also galls on Q. mexicana). Morelia, 14 E, 7000’ (galls, Q. serrulata). Possibly extending throughout a wide area in southwestern Mexico, including Michoacan and Jalisco.

  Life History. — Unknown. This insect produces a gall indistinguishable from that of A. fusus described above. The single female which we have for this species was cut from old galls gathered at the end of December. Whether this insect is a remnant of a spring-emerging; bisexual generation — of a recently-emerged, fall-maturing, agamic generation — or whether there is any alternation of generations in this species is (as with A. fusus) a matter that cannot be determined on the basis of our present material.


description:
  Amphibolips gumia, n. sp.
  Agamic form

  Gall. — Externally a peculiar brownish yellow or russet peach in color, the hairs on the interior of the gall very largely bright russet peach; of fair size, up to 43. mm., averaging near 30. mm. in diameter. 

  Host. — Quercus Emoryi, the shining- and prickly-leaved black oak of lower elevations in southern Arizona. Galls also recorded from Q. hypoleuca (Weld 1326). 

  Range. -- Arizona: Fort Huachuca (types; also galls acc. Weld 1926). Santa Rita Mountains (galls; also galls in U. S. Nat. Mus.). Bisbee (galls, acc. Weld 1926), Santa Catalina Mountains (galls, acc. Weld 1926). Chiricahua Mountains (galls in U, S. Nat. Mus., acc. Weld 1926). Fort Grant (galls in U. S. Nat. Mus., acc. Weld 1926). Apparently confined to the desert mountain ranges of southernmost Arizona and immediately adjacent New Mexico

  Life History, — Galls collected in mid-January had nearly all adults emerged. This, the only American representative of the complex, is a conspicuous object on the black oaks of the desert-mountain ranges of southeastern Arizona. The insect appears to be identical with the insect of A jubatus, from the state of Durango in Mexico; but the galls of the two are very different, those of the Arizona species being of fair size and peculiarly russet peach in color, while those of jubatus are distinctly small and peculiarly brassy yellow in color. Between the ranges of the two are more than 500 miles of Mexican Sierra, occupied by two other species of this complex, namely elatus and nebris, and this seems to justify the use of the gall characters as evidence that the Arizona and Durango insects do not share the the same stock of genes.


description:
  Found in New Mexico November-January, almost always with an exit hole at the tip. The galls are brown and covered with tiny white hairs. 


description:
  Amphibolips (niger) elatus, n. sp.
  Agamic form

  Gall. — Yellow tan and rosy russet, brighter when fresh, weathering dark to brown and grayish black; some galls quite large, with many smaller ones in each series; up to 6.0 mm,, but averaging only 4.0 mm. in diameter. 

  Host. —- Quercus Eduardi, the shining and prickly-leaved black, live oak of the area, a close relative of the American Q. emoryi 

  Range. — Chihuahua: Pedernales, 2 E, 7590’ (Q. Eduardi). 

  Known only from the one locality in more southern Chihuahua, but possibly extending north throughout the state. Replaced still further south in Chihuahua by A. nebris. 

  Life History. — Adults: March 20. April 10, 13, 20. 

  This species, elatus, is probably widespread through the state of Chihuahua. A hundred miles south Of Pedernales, which is the type locality of elatus, there is another species, nebris, on the southernmost border of Chihuahua. But elatus is more closely related to jubatus, the common species in Durango, and not so closely to nebris. From, jabatus, elatus is distiuguishable by the fact that the galls of elatus are very much larger and more tan yellow and rosy russet. 


description:
  Amphibolips jubatus, n. sp.
  Agamic form

  Gall. — A peculiar brassy yellow and rosy russet, weathering greenish brown or darker; the smallest galls in this complex, up to 30. mm'., averaging near 21. mm. in diameter. 

  Host. — Quercus fulva (types); Q. Eduardi, Apparently one species on these two very different black oaks. The first is a small tree with large leaves that are heavily felted underneath: the second is the small- and prickly-leaved black oak related to the American Q. Emoryi, 

  Range. — Durango: Otinapa, 8500' (types. Q. fulva), Patos, 15 W, 8000- (Q. Eduardi), Patos, 15 W, 8500’ (Q. fulva). Apparently confined to the state of Durango, replaced on Q. incarnata in the same area by A. niger.

  Life History. — Emergence dates not recorded; probably in March and April, as in the related species of the complex. 

  This species, jubatus, is the common one throughout the state of Durango. It is replaced in the same area by A. niger on Q. incarnata, Jubatas has its closest relative in elatus, from the southern end (and probably from most of the state) of Chihuahua. Niger is one of three closely related species, nebris, niger, pistrix, which we have from Parral (in the southernmost tip of Chihuahua), from southwestern Durango, and from Zacatecas, respectively. There are evidently two separate lines in the phylogenetic chains, and the two species occuring in Durango .are not as dose relatives as each is to geographically more remote species. The host isolation of the two species in Durango indicates a further difference between them in sensory reactions. The galls of jubatus and niger distinctly differ in color, jubatas galls being a peculiar brassy yellow, those of urger (he same straw yellow that is common in the complex; and the galls of average distinctly smaller — smaller than any others in the complex.


description:
  Amphibolips maturus, n. sp
  Agamic form

  Gall. — Color yellow tan and rosy russet, brighter when fresh, weathering dark to brown and grayish-black; very large, up to 65. mm., averaging nearer 50. mm. in diameter. 

  Host. — Quercus serrulata [castanea] (types), a broader-leaved, serrate black oak. Also on Q. mexicana, the slender- and entire-leaved black oak of the area; and on Q. rossi [castanea], a black, oak with obovate, more reticulate leaves. Possibly on all the black oaks of the area. 

  Range. — Michoacan: Purepero, 5 W, 8500? (Q. serrulata [castanea], types; also on Q. mexicana). Zacapu, 11 E, 8000’ 'Q, serrulata , Jalisco; Sayula, 13 SW, 7700’ (Q. Rossi). Possibly throughout a considerable portion of southwestern Mexico, at least through much of the states of Michoacan and Jalisco.

  Life History. — Adults: .March 25, April 10, 20. The galls which we have seen average larger than in most species. In several of these characters, matures shows relations to the branch of the complex, and not to the nebris-niger-pistrix chain of species.


description:
  Chrysopsis gossypina (Michx.) Elliott subsp. hyssopifolia (Nutt.) Semple (Asteraceae) (Benjamin 1934, as Heterotheca trichophylla (Nutt.) Shinners); Chrysopsis (Nutt.) Ell. spp.(see below); stem galls (reared).

  We have found galls of this species in C . linearifolia Semple, C. scabrella Torr. & Grey, and C. gossypina (and/or gossypina x scabrella?). Adults of P. quadrifasciata have also been collected in association with other species of Chrysopsis in Florida.


description:
  Amphibolips nebris, n. sp.
  Agamic form

  Gall. — Color yellow tan and rosy russet, brigther when fresh, weathering dark to brown and grayish-black; very large, up to 70, mm., averaging near 55. mm. m diameter. 

  Host. — Qnercus Eduardi the shining, prickly-leaved, black live oak of the area, a close relative of the American Q. Emoryi. 

  Range. — Chihuahua: Parral, 12 W, 6800’ (types). Apparently confined to a southernmost portion of Chihuahua, replaced further north and west in the same state by elatus, and by jubatus and niger in Durango.

  Life History. — Adults: March 20. April 5, 15, 22. 

  This insect, nebris, is known only from the single locality west of Parral, in southernmost Chihuahua. It is replaced to the north and probably throughout most of Chihuahua by elatus, and to the south, on most of the oaks in Durango, by jubatus, and on Q. incarnata in Durango by A. niger. But nebria is not closely related to elatas or jubatus, although it is very close to niger and still closer to pistrix from Zacatecas. 

  Nebris differs from niger in having the gall very distinctly larger. 


description:
  HOST. - The larvae feed in Chrysopsis trichophylla, in irregularly shaped galls, usually on the stems, but sometimes at the bases of the flowers, or on the tender growth from the root crowns. The galls are usually compound, and may contain from 1 to 8 separate cells with a single larva or puparium in each. The larva before forming a puparium makes an exit place in the gall, only a thin and easily ruptured covering sealing the emergence hole.


description:
  Amphibolips niger
  Agamic form

  Gall. — Yellow tan and (quite abundantly) rosy russet, brighter when fresh, weathering darker; averaging distinctly small, up to 33, mm. (up to 50. mm. ace. Beutenmuller), but averaging nearer 25. mm. in diameter. 

  Host. — Quercus Incarnata [sideroxyla], a tree form of black oak with entire or undulately toothed leaves. Replaced on other black oaks in the same area by A. jubatus. 

  Range. — Durango: Otinapa, 8500b «Durango» (city or state?) (types). Known only from this one area in the southwestern portion of Durango, but probably extending elsewhere in this part of the Sierra, wherever the host, Q. incarnata, is to be found. 

  Life History. — Adults: January 30. February 1-8. April 15, 22, 27, 

  This species, niger, belongs in the nebris-niger-pistrix series of species, and not to the elatus-jubatus-maturus branch of this complex — even though niger and jabacus may occur in the same localities in the state of Durango. See the discussion under elatus for the distinctions between the two chains, and under elatus for the differences between niger and jubatus. Niger is separable from nebris in its gall very distinctly smaller. From pistrix, niger is distinguishable by its much smaller galls. 


description:
  Amphibolips pistrix, n. sp.
  Agamic form

  Gall. — Golden or reddish yellow and rosy russet, brighter when fresh, weathering dirty brown and grayish black; moderately large, up to 52. mm., averaging near 38. mm. in diameter. 

  Host. — Quercias Eduardi, a small tree with smooth, shining, prickly leaves, a dose relative of the American Q. Emoryi, 

  Range. — Zacatecas: La Mesa, 7000L Known only from this one locality in a southwestern portion of the state of Zacatecas (southwest of Huejucar) 

  Life History. — Adults: April 15. 22, 26. We have this insect only from a single locality in the southwestern portion of Zacatecas, very near the boundary of the most northerly projecting finger of the state of Jalisco. Pistrix is one of the nebris-niger-pistrix chain, of species. The gall averages larger than the largest specimens of niger; and this, in connection with the distinct hosts and geographic isolation of the two, is evidence enough of different genetic constitutions in the populations. 


description:
  Amphibolips nebris Kinsey

  Host: Quercus eduardi

  Range: Chihuahua, Parral

  Gall: Of the type of galls of the “niger complex”: a large densely wooly mass containing a hard woody core in which the larval cell is located (Kinsey 1937; Melika et al. 2011). In A. nebris the gall is large, up to 70 mm; color yellow tan and rosy russet (Kinsey 1937). 

  Comments The characters of this species are representative of those shared by the species of the “niger complex” (Kinsey 1937), being the most important the 16 segmented antennae, mesoscutellum not emarginated posteriorly, sculpture on mesoscutum not coarsely rugose and forewing less heavily infuscate, which together with its morphologically different galls readily differentiates this species from the remaining Mexican species studied herein.


description:
  Biorhiza innocens, n. sp.
  Agamic form

  Gall. — Similar to that of B, eburnea (Bassett). Individual galls rounded but much distorted, flattened on bottom and irregularly compressed, especially on sides coming in contact with other galls; surface fairly smooth, not wrinkled; singly or in clusters, on leaf blades, petioles, or stems. 

  Host. — Quercus Pringlei (types), Q. cordifolia, which are, respectively, scrub and alpine dwarf white oaks. 

  Range, — Tamaulipas: Miquihuana, 25 NW, 7500' (Q. Pringlei and Q, cordifolia), 

  Life History. — Adults: November 27, December 6, 14. January 3, 8, 9, 20, 24, 31. Most of the emergence early in January. 

  This variable-wing, Mexican insect, innocens, is very similar to Bassett's eburnea, which was described from Utah.   From nitellina, the other Mexican species, innocens is best distinguished by its greater distortion from the fundamentally spherical form in the galls.


description:
  Biorhiza nitellina, n. sp.
  Agamic form

  Gall. — Similar to that of eburnea (Bassett), Individual galls quite regularly hemispherical, flattened on bottom, usually not distorted except for some flattening where two calls press together; usually scattered, not particularly clustered, chiefly on leaves, 

  Host. — Quercus repanda [unclear if this refers to modern Q repanda or Q microphylla], the lowest dwarf oak of the area. 

  Range. — Hidalgo: Jacala, 24 SW, 6800' Probably restricted to dwarf white oaks in more northern Hidalgo and immediately adjacent portions of other Mexican states

  Life History. — Adults: December 30. January 2, 8, k 16. February 25. Most of the emergence in the first half of January. 


description:
  Trigonaspis? nitellina (Kinsey), incertae sedis

  Biorhiza nitellina Kinsey
  Trigonaspis zinzala (Kinsey) [A mistake? Sphaeroteras zinzala is listed separately as a valid species in this paper, and this synonymy was not made in the referenced paper]

  [The galls of the two Mexican species considered "incertae sedies" (T innocens and T nitellina) produce identical galls to those of Sphaeroteras.]


description:
  Trigonaspis? innocens, n. comb., Incertae sedis

  Biorhiza innocens Kinsey

  [The galls of the two Mexican species considered "incertae sedies" (T innocens and T nitellina) produce identical galls to those of Sphaeroteras.]


description:
  Biorhiza solita, n. sp. 
  Agamic form

  Gall — Similar to that of B. pulchripennis. Light to rich brown, weathering darker; of medium size, up to 4.2 mm., averaging near 3.5 mm. in diameter. 

  Host. — Q. macrophylla [magnoliifolia] (types), Q. huematophlebia [magnoliifolia], Q. rhodophlebia [rugosa], Q. chihuahuensis, Q. sacame [arizonica], Q. undata, Q. reticulutam [rugosa], Q. potosina, Q. jaralensis [potosina], Q. microphylla. Apparently one species on all of these white oaks.

  Range.— Jalisco: Guadalajara, lu W, 6000' (Q. macrophyda). Guadalajara, 25 S, 6000’ (galls, Q. haemafopldebia, Q. macrophyIla), Magdalena, 4 N, 4300’ (galls, Q. macrophylla). Sayula, 13 W, 7700’ (Q. rhodophlebia). Atequiza, 5 E, 0500’ (galls, Q. haematophlebia). Guanajuato: San Felipe, 20 SW, 8000’ (Q. chihuahuensls; also galls on Q. macrophyda, Q, juralensis). Leon, 20 NE, 9000’ (galls, Q. reticulata, Q. jaratensis, Q. microphyUa). Aguascalientes: Aguascalientes, 35 E. 7000 (Q. macrophylla; also galls on Q. poiosina, Q. undata). Pabelion, 20 W, 7000’ (galls, Q. sacame, Q. undata, Q. inacrophylla). Pabelion, 23 W, 3500’ (galls, Q. potosina, Q, sacame). San Luis Potosi: San Luis Potosi, 15 W, 7000’ (galls, Q. undata). San Luis Potosi, 15 W, 8000’ (galls, Q. potosina). Apparently widespread from San Luis Potosi to the far ends of Jalisco. 

  Life History. — Adults; in most cases probably emerging before the last week of November and December; stray emergence on March 2, 3, 11, and April 1. 

  Solita is the most widespread of me species in the complex, it appears to be one species from the southern corner of the state of San Luis Potosi, through Aguascalientes and Guanajuato, to the far ends of the state of Jalisco: and it is only a minor variation which spreads further east, from Queretaro all the way to Tamaulipas (sec the species soda}. It is apparently one species on all of the while oaks of the area — a total of ten oaks, including dwarfs, scrubs, and tall trees from which the galls have so far been recovered. The galls are often very abundant in these stands of oaks, and they are packed as tightly on the large-leaves of some of the tallest trees as they are on the small leaves of some of the alpine dwarfs. On a leaf of such a large-leaved species of oak as Q. macrophylla, one may find as many as three or four hundred galls, and extensive stands of scrub of this oak may have the leaves so heavily infested that the difference in color of the scrub as a whole is noticeable at considerable distances. All of our collections were made after the last Week of November, most of them in December, and the abundant emergence holes in the galls, as well as the small numbers of the later emergents, make it clear that most of the emergence occurs before the last week of November or early in December. Thus, in spite of our large collections of the galls, we have relatively few insects or solita, and larger series might show Local races or host isolates in what we are now taking to be one, widespread species. 

  Biorhiza socia, n. sp.
  Agamic form

  Gall. — Similar to that of B. pulchripennis. Light brown or even straw brown in color, sometimes richer brown; rather small galls, up to 3.7, averaging 2.9 mm. in diameter. 

  Host. — A tree form of Quercus microphylla; Q. reticulata [rugosa]. 

  Range. — Queretaro: Queretaro, 28 N, 7300’ (Q. microphylla tree). — Hidalgo: Jacala, 7 NE, 5000’ (Q. reticulata; also galls on Q. repanda). Jacala, 5 W, 5800’ (galls, Q. reticulata). — Tamaulipas: Miquihuana, 25 NW, 8500’ (Q. cordifoUa). — Apparently widespread in the Eastern Sierra of .Mexico from Queretaro to Tamaulipas. 

  Life History. — Adults: December 10. January A March 15, 24. April 10. Most of the emergence apparently before the middle of January, stray adults emerging at later dates. 

  This species, socia, is an extension of P. solita. Socia is distinguished by having a smaller gall. Socia ranges widely over a southwestern portion of Mexico, from San Luiz Potosi to the far end of Jalisco. Socia (to judge on the basis of our limited material) ranges nearly as widely in the eastern Sierra, there being some two hundred miles between the localities recorded north of Queretaro and that northwest of Miquihuana in Tamaulipas. Although soda was bred from galls collected on the dwarf scrub, Q. cordifolia. in the mountains northwest of Miquihuana, the remarkable species zinzala is found in the same locality on the taller shrub, Q. Pringlei. 

  Biorhiza stelis, n. sp. 
  Agamic form

  Gall. — Similar to that of B. pulchripennis. Rather light brown, often straw brown, darker only with age; of fair size, up to 4.7 mm., averaging near 3.5 mm. in diameter. 

  Host. — Quercus rhodophlebia [rugosa] (types’), Q, texcocana [deserticola], Q. Purpusli [rugosa]. 

  Range. — Hidalgo: Pachuca, 7 N, 8700’ <Q. rhodophlebia, types). Mexico: Mexico City, 12 W, 8500’ (Q. texcocana). Mexico City, 25 E, TOGO7 (Q. texcocana). Jildtepec, 7 NW, 9500’ (galls, Q. Purposit). Apparently confined to the southern end of the state of Hidalgo, and to the mountains rimming the northern half of the Valley of Mexico. Replaced on Q, repanda in the same area by B. tanos, and replaced at the southern end of the Valley of Mexico by B. tricosa

  Life History. — Adults: March 15, 20, 23, 24. April 10. The entire record thus between mid-March and mid-April. 

  The abundance of this species in the mountains rimming the northern half of the Valley of Mexico is so great that it was a simple matter to gather the very large series which we have in our collection. Unlike some of the other Mexican species of this complex, the insects of the present species do not emerge until March and April. stelis is confined to the taller oaks (Q. texcocana, Q. rhodophlebia) of the area. Under these taller trees, in the very same localities, on the low scrub oaks, Q. repanda, there is a very similar species, B. tanos of this same complex. 

  Biorhiza tarasco, n. sp.
  Agamic form

  Gall. — Similar to that of TT pulchripeofiis. Light yellow brown, of moderate size, up to Id im, averaging nearer 3.5 mm. in diameter. 

  Host. — Quercus conglomerata [rugosa]

  Range. Michoacan: Morelia, 14 E, 7000J (types). Possibly restricted to a portion of the mountains of Michoacan.

  Life History. — Adults: March 15, 25. April 10., 

  In all other characters the species is typical of the complex, and its gall is indistinguishable from the galls of the other species of more southern Mexico. There can be no question that tarasco is one of the links in this complex. 

  Biorhiza tricosa, n. sp.
  Agamic form

  Gall. — Similar to that of B. pulchripennis, Rather light brown, often straw-brown in color, darker only with age; of moderate size, up to 4,0 mm., averaging 3.0 mm. in diameter. 

  Host. — Quercus rhodophlebia [rugosa] (types), Q. texcocana [deserticola]. Probably on all white oaks, except the low dwarfs in the area. 

  Range. — Mexico: Mexico City, 20 S, 9200'’ (Q, rhodophlebia, types). Mexico City, 17 S, 8200’ (Q. texcocana). Apparently confined to the southern end of the mountains rimming the Valley of Mexico.

  Life History. — Adults: March 2, 10, 24, 30. 

  Biorhiza ulcus, n. sp.
  Agamic form

  Gall. — Similar to that of B. pulchripennis. Light to medium brown, of moderate size, up to 4.0 mm., averaging near 3.5 mm. in diameter. 

  Host. — Quercus nudinervis (types); Q. macrophylla. [both magnoliifolia]

  Range. — Guerrero: Taxco, S NE, 8000' (Q, nudinervis, Q. macrophylla). Apparently confined to a northeastern portion of the .state of Guerrero. 

  Life History. — Adults: March 20. 


description:
  Biorhiza tanos, n. sp.
  Agamic form

  Gall. — Similar to that of B. pulchripennis. Light to medium brown in color (no darker); of medium size, up to 4.0 mm, averaging nearer 3.2 mm. in diameter. 

  Host. — Quercus repanda, the lowest dwarf oak of the area. Replaced on all the taller tree species in the region by B. stelis and B. tricosa. 

  Range. — Hidalgo: Pachuca, 7 N, 8700' (types). Mexico: Mexico City, 32 E, 10,6007 Mexico Citv, 20 S. 9400' 

  Apparently one species on the dwarf oaks throughout the mountains rimming the Valley of Mexico. 

  Life History. — Adults: March 6, 18, 24, 25, 23 Nearly all of the recorded emergence in the last week of March. 

  In the mountains rimming the Valley of Mexico, on the taller tree species of oak there are two species of the present complex: stelis at the northern end, and tricosa at the southern end of the Valley. Throughout the entire area there is one species, tanos, on the low dwarf oaks of the Q, repanda complex. 


description:
  Sphaerotheras solitum (Kinsey) n. comb.

  [Photos of this gall appear on page 16 of the pdf]

  Biorhiza solita Kinsey, 1937: 449.
  Biorhiza ulcus Kinsey, 1937: 457.
  Biorhiza urcea Kinsey, 1937: 458.
  Biorhiza socia Kinsey, 1937: 448.
  Cynips socia (Kinsey) Pujade-Villar y Ferrer-Suay, 2015: 12.
  Sphaerotheras solitum (Kinsey) n. syn.
  Sphaeroteras stelis (Kinsey) n. syn.
  Sphaeroteras tarasco (Kinsey) n. syn.
  Sphaeroteras tricosa (Kinsey) n. syn.
  Sphaeroteras ulcus (Kinsey) n. syn.
  Sphaeroteras urcea (Kinsey) n. syn.
  Sphaeroteras socia (Kinsey) n. syn.

  [Attending to the morphological characters and the host plants, we consider there to be three species of Sphaeroteras in Mexico: S solita, tanos, and zinzala. We cannot exclude the possibility that, in the future, the color forms S solita and S tanos will be considered the same species. For the moment, other than color, these species are separated by the host plants in which their galls are found; thus, S solita produces galls on multiple species of Quercus (arizonica, chihuahuensis, deserticola, jaralensis, magnoliifolia, microphylla, rugosa, and undulata [should be undata?]), while S tanos has only one host on which S solita is not found (Quercus repanda). Sphaeroteras zinzala has been collected in two hosts distinct from the other two species of Sphaeroteras mentioned (Quercus intricata and pringlei).

  The galls of the three species of Sphaeroteras from Mexico are indistinguishable. Kinsey (1937) mentioned that they are like those of B pulchripennis. They are characterized by being more or less circular, between 3-4.5 mm in diameter, being located in the lower side of the leaves sometimes in great numbers, being attached to the midrib or secondary veins, being yellow to light brown, having the surface smooth and glossy covered in a short pubescence easily rubbed off with a few short darker bumps, having the base more or less flat with a longitudinal depression corresponding to the point where it meets the leaf vein; the larval cell is eccentric, attached to the walls of the gall by fine white filaments.]


description:
  Sphaerotheras tanos (Kinsey) n. comb.

  Biorhiza tanos Kinsey, 1937: 453.

  [Attending to the morphological characters and the host plants, we consider there to be three species of Sphaeroteras in Mexico: S solita, tanos, and zinzala. We cannot exclude the possibility that, in the future, the color forms S solita and S tanos will be considered the same species. For the moment, other than color, these species are separated by the host plants in which their galls are found; thus, S solita produces galls on multiple species of Quercus (arizonica, chihuahuensis, deserticola, jaralensis, magnoliifolia, microphylla, rugosa, and undulata [should be undata?]), while S tanos has only one host on which S solita is not found (Quercus repanda). Sphaeroteras zinzala has been collected in two hosts distinct from the other two species of Sphaeroteras mentioned (Quercus intricata and pringlei).

  The galls of the three species of Sphaeroteras from Mexico are indistinguishable. Kinsey (1937) mentioned that they are like those of B pulchripennis. They are characterized by being more or less circular, between 3-4.5 mm in diameter, being located in the lower side of the leaves sometimes in great numbers, being attached to the midrib or secondary veins, being yellow to light brown, having the surface smooth and glossy covered in a short pubescence easily rubbed off with a few short darker bumps, having the base more or less flat with a longitudinal depression corresponding to the point where it meets the leaf vein; the larval cell is eccentric, attached to the walls of the gall by fine white filaments.]


description:
  Biorhiza zinzala, n. sp.
  Agamic form

  Gall. — Similar to that of B. pulchripennis, but distinct in shape; medium to dark brown in color; shaped like an inverted flask, attached by a cylindrical base, averaging near 0.7 mm. in diameter, the base immediately expanding into a swollen, elongate, flask-shaped or more nearly spherical top which may be up to 3.0 mm. but averages nearer 2.3 mm. in diameter, the exit hole usually at the very tip of the gall. 

  Host. — Quercus intricata, Q. Pringlei (two scrub oaks not clearly distinct in the type locality of zinzala). 

  Range. — Tamaulipas: Tula, 22 N, 6100* (types, Quercus intricata and Q. Pringlei). Miquihuana, 25 NW, 7500’ (Q. Pringlei). Miquihuana, 7 SE, 6000’ (Q. Pringlel). Probably confined to a portion of the eastern Mexican Sierra, in and adjacent to the southwestern corner of Tamauli.pa&.

  Life History.— Adults: February 5, 11. March 10, 15. 

  This insect is probably confined to a portion of die eastern Mexican Siena centering in the southwestern comer of Tamaulipas. The two localities from which we have this species, zinzala, are some thirty miles apart — the two collections made four year's apart, on expeditions which penetrated this part of the Eastern Sierra from opposite directions. The oak in this region, occurs in narrow bands which may wind, at particular altitudes for each species, for considerable distances about the mountains sides, though the vertical spread is never great. Semi-tropic and desert wastes limit the lower extent of these oaks; in many of the ranges wind-swept and often cold mountain divides prevent the spread of most of the fauna and flora from one side to the other of the same ridge. The frequent limitation of moisture to nail canyons increases the possibility that each cynipid species is an endemic restricted to some very limited portion of the mountains; and yet we know some cynipids which range a hundred miles or more in this region, The area is so difficult to penetrate that we have not vet learned enough about it to predict the range of an particular element of its fauna. like the present species zinzala. 

  It is to be noted that the very low dwarf, Q. cordifolia, which forms dense mats on the highest ridges in this area, bears B. socia (see Figure 4) of the present complex. Zinzala occurs at slightly lower elevations on the taller scrub oaks, Q. intricata and Q. Pringlei (two oaks which are not always separable in every locality).


