REPORT OF THE STATE ENTOMOLOGIST I918 23I 



The larvae appear to desert the gall in the fall, the adults issuing 

 the follow-'ng spring and presumably ovipositing upon the develop- 

 ing leaves. This gall has been recorded by Walsh as rather abundant, 

 though local, on the leaves of Salix humilis near Rock Island, 

 111. A smaller gall, apparently the same, was also found by Walsh 

 on the fo'iage of S. discolor. 



GalL The gall (pi. 12, fig. i) is a very characteristic subconic 

 enlargement arising in clusters from the midrib or some of the prin- 

 cipal veins of the leaf. The gall is about 2 mm in diameter, greenish 

 yellow, monothalamous, subglobular and tapering to a truncate, 

 frequently lipped, free extremity. The presence of the gall on the 

 upper surface of the leaf is indicated by a small point or nipple. 



Larva. Length 1.5 mm, orange colored, the breastbone small and 

 indistinct. 



Female. Length 2.5 mm. Antennae extending to the second 

 abdominal segment, sparsely haired, pale yellowish orange; fourteen 

 segments, the fifth subsessile, a very short stem, the basal enlarge- 

 ment cylindric, with a length over twice its diameter; low circumfila 

 occur near the basal third and subapically; terminal segment slightly 

 reduced, tapering, broadly rounded. Palpi; the first segment with 

 a length more than twice its diameter, rectangular, the second 

 broadly oval, with a length one-half greater than its diameter. 

 Mesonotum dark brown, the submedian lines thickly haired. Scu- 

 tellum reddish brown, postscutellum reddish. Abdomen dark red, 

 sparsely haired; ovipositor fuscous yellowish. Wings hyaline, 

 rather narrow; costa dark brown, the third vein just before the apex. 

 Halteres fuscous yellowish, fuscous subapically. Coxae, femora and 

 tibiae fuscous yellowish, the tarsi darker, almost black; claws rather 

 short, stout, strongly curved, the pulvilli distinctly longer than the 

 claws. Ovipositor about one-third the length of the abdomen, 

 rather stout, the terminal lobes long, stout, narrowly and irregularly 

 oval. Type Cecid. aiySs. 



ODONTODIPLOSIS Felt 

 1908 Felt, E. P. N. Y. State Mus. Bui. 124, p. 404 



1910 Rubsaamen, E. H. Zeitsch. Wissenschaft. Insektenbiol.,' 15:287 



191 1 Felt, E. P. N. Y. Ent. Soc. Jour., 19:61 



1 91 3 Kieffer, J. J. Gen. Insect., fasc. 152, p. 203 



This genus is erected for the separation of certain species allied to 

 Cecidomyia, which may be distinguished therefrom by the triarticu- 

 late palpi and the conspicuous serrations on the somewhat conical 

 ventral plate or harpes. Type Cecidomyia karner- 

 e n s i s Felt. 



Key to Species 

 a Fifth antenna! segment having the basal portion of the stem with a length 

 about one-half greater than its diameter 



b Length .75 mm; abdomen reddish yellow 



k a r n'^e r e n s i s Felt, C. 27 



