Dec, 1920 Bulletin of the Brooklyn Entomological Society 123 



hind tibia often with three bristles ; arista almost bare 

 except on apical half ; antennae largely or entirely 



rufous yellow triseta Malloch 



— • Anterior lateral angles of thorax black, scutellum tes- 

 taceous at apex ; tibial bristles comparatively short and 

 weak ; hind tibia with two posterodorsal bristles ; 

 arista with the hairs on basal half at least as long as 

 its basal diameter ; third antennal segment largely or 

 entirely infuscated fuscofasciata Malloch 



11. Abdominal tergites each with a distinct narrow fuscous 



fascia on posterior margin ; hypopygium large. 



vittiger Zetterstedt 



— Abdominal tergites without fuscous fasciae; hypopygium 



small geniculata Bouche 



12. Posthumeral bristle duplicated, numerous hairs usually 



laterad of posthumeral ; hind tibia with three or more 

 anterodorsal bristles ; third wing-vein always bare at 

 base 13 



— Posthumeral bristle not duplicated, the area laterad of it 



bare or with a few setulose hairs near bristle ; hind 

 tibia with two anterodorsal bristles ; third wing-vein 

 usually with a few weak hairs at base 16 



13. Palpi blackened at apices ; abdomen blackish gray, with 



a black dorso-central vitta; fifth sternite with the 

 processes tapered to apices, the inner margin of each 

 concave near middle hyoscyami Panzer 



— Palpi entirely pale ; abdomen reddish testaceous, with a 



darker dorso-central vitta ; fifth sternite with glossy 

 processes which are not tapered to apices, but usually 

 slightly dilated or knobbed at tips 14 



— Palpi entirely pale; processes of fifth sternite not glossy, 



tapered to apices, which are slightly pointed 15 



14. Hind tibia with three posterodorsal bristles ; scutellum 



entirely, fore femora largely black ; processes of fifth 

 sternite blackened apically bicolor Wiedemann 



— Hind tibia with two posterodorsal bristles ; scutellum 



partly and fore femora largely or entirely reddish tes- 

 taceous ; processes of fifth sternite blackened apically. 



calyptrata Zetterstedt 



— Hind tibia with two posterodorsal bristles ; thorax en- 



tirely brownish black ; all femora testaceous, darker in 

 middle ; processes of fifth sternite not blackened 

 apically minuta Malloch 



15. Third antennal segment with a transverse pale area at 



base on inner side which is slightly elevated and pre- 



