June, 1917 Bulletin of the Brooklyn Entomological Society 53 



Little if any yellow hair on legs ; frequently no yellow on abdomen, 



thoracica Fabr. 



6. Hair in front of the halters wholly black; that in front of the wings 



also black; abdomen with yellow band near tip sackeni n. sp 



Hair in front of the halters j^ellow, at least in upper part 7 



7. Hair in front of the wings yellow, or with only a few black hairs. . 8 

 Hair in front of the wings largely black 12 



8. Abdomen with more or less red hair behind -.fernaldi Back, 



Abdomen without red hair 9 



9. Scutellum, as rest of body, with j^ellow hair unicolor Will 



Scutellum black haired 10 



10. All tibis and tarsi red haired above; about apical half of abdomen 



yellow partitor n. sp 



No tibiae nor tarsi red haired 11 



11. The yellow on abdomen near tip; western species . . . .calif ornica n. sp 

 The yellow (if any) on abdomen mostly toward base; eastern species 



grossa Fabr 



12. Posterior part of thorax with red hair insignis n. sp 



Not red haired on thorax 13 



13. Scutellum yellow haired 14 



Scutellum black haired 15 



14. Abdomen with yellow hair near tip divisor n. sp 



Abdomen wholly black flavicollis Say 



15. Very large species ; in male front and mid legs with very long yellow 



hair, and some yellow on hind femora above; wings very dark, 



lata Macq. 

 Moderate size, wings paler, in male no yellow on hind femora .... 16. 



16. Western species I7- 



Eastern species 18. 



17. Male with red hair on abdomen; female with hair in front of wings 



black astur O. S. 



Male without red on abdomen ; female with yellow hair interspersed 

 with the black at base of wings Colombia Walk. 



18. No yellow hair on the abdomen virginica n. sp. 



Yellow hair on the abdomen 19. 



19. Superior male appendages deeply excavate on the outer edge ; yellow 



hair in female extends more to base of abdomen, .champ laini Walt. 

 Superior male appendages but little excavate on outer edge ; in female 

 yellow hair does not usually extend so far toward base, 



posticatus Say. 

 Dasyllis virginica n. sp. — In general appearance similar to D. flavicollis, 

 but the scutellum is without yellow hair; the basal abdominal segment is 

 black haired on the sides, as are the other segments (in flavicollis there is 

 some yellow hair on sides of the basal segment) ; the body of the male is 

 broader than usual in flavicollis, and the superior appendages are more 

 blunt pointed. Length 18 mm. ' 



