48 PROCEEDINGS OF THE NATIONAL MUSEUM vol.83 



4. Parafacial hairs black ; third antennal segment widest near 



apex with anterior margin straight, hardly longer than second 

 segment ; parafrontals without any large bristles outside 



main row (California) (1) miscelli (Coquillett). 



Parafacial hairs wliite; third antennal segment strongly convex 

 on anterior margin and distinctly exceeding length of second ; 

 a secondary row of frontal bristles outside main row on 

 widest part of parafrontal (Texas, Arizona) (2) parksi, new species. 



5. Palpi .ibsent 6. 



Minute palpi present; parafrontals black, subshining; face, 



cheeks and beard golden ; apex of fourth abdominal segment 

 orange-yellow (Chile) (7) australis (Townsend). 



6. Scutellum with three or four marginal bristles 7. 



Scutellum with only two marginals ; third antennal segment 



slightly convex or almost straight on front edge ; frontal 

 stripe narrower than one parafrontal on upper half; fourth 

 abdominal segment red above on apical third to half (Ari- 

 zona, California) (4) scutellaris, new species. 



7. Fourth abdominal segment red at least on upper surface 8. 



Fourth abdominal segment black ; frontal stripe wider than one 



parafrontal on entire length ; cheek three-fourths eye height ; 

 inner forceps of male genitalia moderately long, slender on 

 apical half with a raised median line behind (Arizona). 



(5) conformis, new species. 

 8. Abdomen black, anal segment wholly red and sharply con- 

 trasted with preceding ones; parafrontals pale or yellow in 

 ground color, thinly pollinose ; front about one and one-half 



times width of eye (United States, Mexico) (11) hirsuta (Townsend). 



Abdomen broadly red on sides, fourth segment entirely con- 

 colorous above ; ground color of parafrontals obscured by 

 rather dense gray pollen except at vertex ; front approxi- 

 mating twice width of eye; apical segment of proboscis un- 

 usually slender and about equal to height of head (Cal- 

 ifornia) (6) geminata, new species. 



9. Palpi absent 10 



Rudimentary' palpi present; four postsutural dorsocentrals 



(Texas, Arizona) (16) incongrua, new species. 



10. Cheeks clothed with black hairs or bristles 11. 



Cheeks wholly pale haired, about one-third eye height ; femora 



yellow ; intermediate fore tarsal segments in female broadly 



dilated (Cuba) (9) buccata, new species. 



11. Three dorsocontral bristles 12. 



Four dorsocentrals ; male with orbital bristles. 



(16) incongrua, new species. 



12. Epaulets reddish or yellow 13. 



Epaulets black; scutellum red, bearing four marginals of 



unequal size, disk with 10 or 12 erect bristles besides a 

 reclinate discal pair; fourth abdominal segment black tinged 

 with red above on basal margin ; parafrontals black in ground 

 color before vertex; inner forceps of male genitalia strongly 

 bowed forward (Oregon, California) (15) torosa, new species. 



