PROC. ENT. SOC. WASH., VOL. 22, NO. I, JAN., 1920 15 



Promachus fitchii Osten Sacken. . .Conn., Nebr., Fla. 



Asilus orphne Walker Me., Mont., : . C. 



Asilus antimachus Walker Ohio, Kans., Va. 



Asilus cacopilogus Hine N. J., Nebr., Tex. 



The writers gratefully acknowledge the courtesy of the follow- 

 ing persons in supplying records or in permitting the examina- 

 tion of collections owned by them or in their charge: F. R. Cole, 

 C. T. Greene, J. S. Hine, F. Knab and W. R. Walton. 



SYNOPSIS AND ANNOTATED LIST OF THE SPECIES. 



Key to the Stibfamilies. 



A. Marginal cell of wing open. 



B. Abdomen and legs very slender, hind femur much elongated and 



swollen toward apex; palpi one-jointed Leptogastn>i:n'. 



BB. Abdomen and legs not unusually slender; palpi two-jointed. . 



Dasypogo)i 



AA. Marginal cell of wing closed. 



C. Antenna without terminal arista; palpi two-jointed . .Laphriimu'. 

 CC. Antenna with long terminal arista; palpi one-jointed. .Asilinnc. 



Leptogastrinae. 



Key to the Genera. 

 A single genus .Leptognsh-r. 



Leptogaster Meigen. 

 Key to the Species. 



A. No empodia; hind femur with dark band before broadest part; hind 

 tibia with bands at base and middle dark; thorax pinkish, antennae 



pale annnlatns. 



AA. Empodia present. 



B. Hind tibia dark for a considerable distance; hind femur dark or dark 

 banded. 



C. Legs mostly dark, very slender; antennae dark tennis's. 



CC. Legs mostly pale. 



D. Dorsum of thorax wholly shining black; hind femur with 

 apical dark band and another over beginning of s\v<l 



ling atridorsalis . 



DD. Dorsum of thorax not wholly shining black. 



E. Dorsum of thorax with three polished black stripes; hind 

 femur with dark band over swelling; antennae pak 



virgatus. 



