IIO NEW YORK STATE MUSEUM 



ally with yellowish hairs, the submedian lines thickly clothed with 

 diverging yellowish hairs. Scutellum dark brown with a few 

 yellowish setae apically ; postscutellum dark brown. Abdomen dark 

 brown, sparsely clothed with fine hairs, the segments margined 

 posteriorly with longer setae; venter sparsely clothed with short, 

 yellowish setae. Wings hyaline, costa dark brown. Halteres yel- 

 lowish basally, fuscous apically. Legs rather variable brown, tarsi 

 dark brown ; claws long, slender, strongly curved, the pulvilli longer 

 than the claws. Genitalia ; basal clasp segment stout ; terminal clasp 

 segment slender, tapering; dorsal plate long, broad, deeply and 

 narrowly incised; ventral plate broad, tapering, broadly and deeply 

 incised, the lobes long, narrow, tapering, obtuse. Harpes broad at 

 base, tapering, obtuse, entire surface evenly covered with short, stout 

 setae ; style short, stout, broadly rounded. 



Female. Length 4 mm. Antennae extending to the third abdo- 

 minal segment, dark brown, the basal segment thickly clothed vent- 

 rally with silvery scales ; 22 or 23 segments, the fifth subsessile, 

 subcylindric, with a length about twice the diameter ; the distal two 

 or three segments in the specimen described are fused into a spiral 

 compound mass, the apex obtuse. Abdomen dark reddish brown, 

 the segments sparsely margined posteriorly with pale yellowish 

 hairs, the incisures deep red, the ovipositor pale fuscous yellowish, 

 the venter dull reddish brown, the median sclerites a dark brown 

 and sparsely clothed with short, silvery hairs. Wings hyaline, costa 

 dark brown; the ovipositor at least one-half the length of the 

 abdomen; terminal lobe long, broad, acute. Otherwise nearly as 

 in the male. Type Cecid. a 1399. 



Rhabdophaga cornuta Walsh 

 1864 Walsh, B. D. Ent. Soc. Phila. Proc, 3:624-26 (Cecidomyia) 

 1870 Amer. Ent., 2:299 (Eurytoma studiosa Say, 



reared, Cecidomyia) 



1906 Felt, E. P. Ins. Affect. Prk. & Wdld. Trees, N. Y. State Mus. 



Mem. 8, 2735 



This species appears to inhabit willow stems in very much the 

 same way as the preceding midge. It is possible that they are 

 closely related. The larva, according to Walsh, bores cylindric holes 

 into the solid wood of the largest willow, Salix, stems. They 

 generally work rather close to the point from which galls of R. 

 brassicoides arise and usually where the growth of a good 

 sized willow stem has been arrested. These midge larvae produce 

 elongate, oval swellings. The interior of the galleries is always 

 much blackened and discolored. The first sign of infestation is 

 usually the circular exit hole. It is recorded as very rare near 

 Rock Island, 111. We have observed a very similar gall rather 

 commonly on willow at West Nyack, N. Y., though we have been 

 unable to rear a midge therefrom. Eurytoma studiosa Say 

 was reared from the gall of this species. 



