18 PROC. ENT. SOC. WASH., VOL. 22, NO. I, JAN., 1920 



Dasypogoninae. 



Key to the genera. 

 A. Front tibia with a terminal claw-like spur. 



B. Face flat or concave, oral margin prominent, bristly Deromyia. 



BB. Face convex below, oral margin not prominent, hairy. 



C. Third joint of antenna excised on upper side before apex, the 



lobe spinose Taracticm. 



CC. Third joint of antenna not excised; with a small terminal style. . . 



Nicodes. 



AA. Front tibia without terminal spur. 



D. Fourth posterior cell closed; abdomen cylindrical, elongate; third 



antennal joint with excision on inner half Dizonias. 



DD. Fourth posterior cell open. 



E. Antenna apparently five -jointed Ceraturgus. 



EE. Antenna three (or apparently four) jointed; third joint may have 

 a terminal style. 



F. Style thick, appearing like a fourth joint. Dioctria. 



FF. Style more slender than third joint. 

 G. Face distinctly swollen in profile. 



H. Face swollen below Lasiopogon. 



HH. Face swollen to base of antennae Cyrlopogon. 



GG. Face flat or only gently convex. 

 I. Hind metatarsi much enlarged. 



J. Head much broader than high, goggle-like; bare 



species Holcocephala. 



JJ. Head little broader than high, not goggle-like; hairy 



species Holopogon. 



II. Hind metatarsi not enlarged. 



K. Face flat or concave, narrowed above, bare, except 



on oral margin Stichopogon. 



KK. Face rounded, largely hairy; not narrowed above. . 

 Heteropogon. 



Ceraturgus Wiedemann. 



C. cruciatus Say. There are numerous records of this at least 

 not common species; season, June 5 to July 26. V. P. I. 



Dioctria Meigen. 

 Key to the Species. 

 A. Third joint of antenna much longer than first and second together; style 



long banksi 



AA. Third joint of antenna not longer than first and second together; style 

 short bwis. 



D. banksi Johnson. Originally described from this region under 

 the name longicornis Banks, some of the following specimens 

 listed being the type material as is the case also with var. tibialis 

 Banks. Plummers Island, Md., June 11, W. Palmer; June IS, 



