48 Bulletin Wisconsin Natural History Society. [Vol. 8. No. 1. 



2. Vertex rugulose ; legs more or less black cecidomyiae Ashm. 



Vertex transversely aciculate : legs yellow, rarely somewhat 



mfuscated noveboracensis sp. nov. 



Eritrissomerus noveboracensis sp. nov. 

 Male. Length 2mm. Black ; legs yellow, sometimes mfuscated 

 on the hind femora: antenna? piceous brown, scape lighter brown. 

 Head slightly wider than the thorax, very much contracted behind the 

 eyes ; about twice as wide as thick. Vertex and occiput finely trans- 

 versely aciculated. Lateral ocelli more than their diameter removed 

 from the eye-margin, about as close as to the median ocellus. Front 

 punctate or slightly transversely aciculate, with a smooth, median, 

 slightly impressed line below the anterior ocellus. Face transversely 

 striate. Cheeks sparsely punctate. Mandibles ferruginous. Antennae 

 10-jointed ; scape reaching to the median ocellus ; pedicel obovate, twice 

 as long as the first flagellar joint which is half as long and only about 

 one-third as wide as the greatly swollen second joint; two following 

 joints narrow, each about one-half longer than wide ; following growing 

 shorter except the last which is longer, narrower and acuminate. Meso- 

 notum elongate, with two very distinct, complete parapsidal furrows 

 which are closely approximated ; its surface shining, faintly punctulate. 

 Scutellum very convex, rounded, with a very distinct carinate margin. 

 Pletme smooth, shining; the mesopleura with a large impression below 

 and with a few coarse stria? just beneath the tegula?. Collar below on 

 the sides closely punctulate. Metapleura thinly hairy, not striated, with 

 a short basal carina above, which forms a. triangular area with a second 

 oblique carina lower down on the metapleura. Abdomen elongate, 

 pointed, about one-third longer then the head and thorax united. 

 Petiole and basal third of second segment finely striated, the stria? on 

 the sides of the second segment shorter ; second segment nearly as long 

 as the following united. Legs bright or honey yellow ; coxae black and 

 the four posterior tibia? sometimes infuscated. Wings hyaline, with 

 a slight yellowish tinge. 



Described from two specimens (ai36o) bred by Dr. E. P. 

 Felt at Albany. New York. April 5th, 1907 from a Cecidomyid 

 gall. A third specimen (31339) was reared May 7, 1907. 



The species looks very much like certain species of Polygnotus, 

 but the peculiar swollen condition of the second flagellar joint, 

 characteristic of males of the present genus will readily serve to 

 distinguish from that very extensive genus. 



