Descriptions of New Cynipidm 201 



carinas running to the base of the abdomen. Abdomen^ with 

 2d segment occupying fully half of the dorsum, Bd segment 

 about one third as long as the 2d, seven segments visible, ovi- 

 positor sheaths projecting above the dorsum, venter consider- 

 ably extended posteriorly, the last two characters reminding 

 one of Ceroptes sp. Wings hyaline, with distinct dusky patch 

 surrounding the second transverse nervure, radial cell entirely 

 open, the radial and subcostal nervures ending abruptly just 

 before reaching costal margin, the subcostal, radial, and first 

 and second transverse nervures stout, the others very slight, 

 the areolet, consequently, rather faint but of medium size. 



Described from two females taken while ovipositing in 

 galls as above mentioned and one specimen captured at large; 

 all from Ames, Iowa. 



Genus Aulax Haktig. 



A. bicolor n. sp. 



Gall-fly. — Female. — Head and thorax black, feet and 

 abdomen yellow-ferruginous; length 2| mm. 



Head black, shading into rufous between the eyes and 

 mouth, mandibles except tips rufous, face finely wrinkled, 

 vertex and occiput finely sculptured, the sculpturing of the 

 gense making them appear to be covered with scales like the 

 body of a fish, ocelli on a flat or somewhat depressed surface; 

 antennae dark rust-brown, darkest toward the tips, 13-jointed, 

 joints 3 and 4 equal in length, last joint as long as the two 

 preceding. Thorax black, shoulders rufous, mesothorax finely 

 sculptured, opaque, clothed with sparse recumbent pubescence, 

 parapsidal grooves very distinct and rather deep, median groove 

 very short and much broadened at scutelium so as to be almost 

 triangular. The lateral grooves appear as polished lines only, 

 and the two parallel lines from the collar are rather indistinct; 

 pleurae densely and rather coarsely aciculate. Scutelium black, 

 with two small, shallow, oblique fovete, rather coarsely rugose, 

 the surface somewhat obscured by pubescence. Abdomen 

 rufous, shining, 2d segment occupying about one third of 

 dorsum, 3d joint a little more than half as long as the 2d, fol- 

 lowing joints to the 7th gradually shorter, joints 3-7 inclusive 



