GALL APHIDS OF THE ELM. 20I 



(Three specimens examined have joints 4 and 5 very imperfectlv sep- 

 arated, causing the antennae to appear as 5-jointed). Wings as de- 

 scribed by Walsh, the stigma being well rounded and pale. (In three 

 specimens examined, the third discoidal of the front wing is simple and 

 precisely as in Pemphigus; in one specimen, the first discoidal is want- 

 ing on both front wings, and in another the fork of the third discoidal 

 is wanting on the left one). Basal joint of tarsus rather short; tarsal 

 claws only moderately strong. 



"Third generation. — The young from the winged female, after being 

 freed from the pellicle in which they were born, have stout five-jomted 

 antennae, the joints subequal; stout but short promuscis reaching to 

 hind coxae ; rather large compound eyes. Proportions and shape of 

 young Phylloxera. 



"True female: Legs short and the basal joint of tarsus rudimentary; 

 antennae short, four-jointed, smooth, joints subequal, the third some- 

 what longest. Mouth rudimentary. Described from skins surrounding 

 impregnated egg. Males unknown." 



Thomas (1879) gives for this species besides a systematic 

 discussion, the following characterization : 



"Glvphiiia iihiiicola. Fitch. The Aphis of the Elm-leaf Cockscomb 

 gall. ' 



"This species forms the cone-shaped galls, so common on the upper 

 side of the leaves of young white elms. These galls, which are often 

 an inch or more in length, vary in height, from one to three-quarters 

 of an inch ; they are compressed and grooved on the sides, and perpen- 

 dicular, showing tooth-like, conical projections at the top: opening by a 

 long slit on the under side. The inside is wrinkled perpendicularly into 

 deep plaits or folds, and occupied by one female and her progeny, some 

 of which may often be seen strolling out on the under side of the leaf. 

 "My examinations of these insects show the characters of the species 

 to be as follows : 



"IVingcd individual.— Length of body about .05 inch, to the tip of 

 the closed wings .08 inch, thorax black; the abdomen dull black or 

 greenish black above; paler, obscure green beneath; slightly pruinose. 

 Antennae very short, scarcely reaching beyond the insertion of the fore- 

 wings ; first and second joint very short; third much the longest, about 

 equal in length to the three following taken together, fifth and sixth 

 about equal, all except the basal joints transversely corrugated. Wings- 

 transparent, resting somewhat flatly on the abdomen while in the gall, 

 but after the specimens have been removed for a while, will assun^e the 

 usual erect position, the coslal and sub-costal veins dark; the latter 

 robust and undulating; stigma prominent; the first and second discoidal 

 veins are close together; the third obsolete at base, emits the fork 

 about midway its length (counting to the imaginary point of insertion). 

 No honey-tubes ; the abdomen expanding near the tiji. 



"The zvinglcss individxials are very short, broadly ovate, and very 

 convex; olive green, covered slightly with a white powder; antennae 

 and legs verv short." 



