172 D. W. COQUILLETT. 



17. — Tonieiitum on base of wings iu front wliolly yellow, only the pile or bristles 



of the front edge black 18. 



Tonientnm on base of wings in front largely or wholly black ; that on the 

 occiput usually white; base of wings destitute of an epaulette of silvery 



scales in the male 19. 



18. — Bristles of thorax black; light colored tomentum of abdomen white; pile 



of sides of abdomen abundant, depressed 60. liircina. 



Bri.stles of thorax yellow; light colored tomentum of abdomen yellowish, 

 except a cross-band of white tomentum on apex of the first segment : 

 pile on sides of abdomen, except on the first two segments, very sparse. 



12. tiirbata. 

 19. — Claws of front tarsi nearly one-third as long as those of the middle tarsi. .20. 

 Claws of front tarsi two-thirds as long as those of the middle tarsi; last 

 segment of abdomeii of male destitute of silvery tomentum. 



15. siipiiia. 

 20. — Last two or three segments of the abdomen provided with dai'k reddish 

 brown tomentum, which is noticeably darker than the remaining to- 

 mentum, except that which is black 6. coiisossor. 



Last two or three segments destitute of yellowish or brown tomentum. 



which is darker than that on the remaining segments 21. 



21. — Wings, except in the costal cell, pure hyaline 7b. lateralis. 



Wings tinged with brown in the first liasal, marginal, first submarginal and 



first posterior cells 74. launui^. 



22. — Front tibise provided with bristles 23. 



Front tibiiB destitute of bristles 26. 



23. — Tomentum of abdomen dense, forming cross-bands; sides of segments five 

 and six usually provided with black pile; base of wings of male fur- 

 nished with an epaulette of silvery scales; last abdominal segment 



destitute of silvery scales 24. 



Tomentum of abdomen sparse, not forming distinct cross-bands; pile of 



dorsum and sides abundant, bushy 9. f'ulTiaiia. 



24. — Venter destitute of cross-bands of black tomentum ; the yellowish pile and 

 tomentum of abdomen sometimes dark, but never deep golden ; the 



pile mostly erect and bushy 61. agrippiiia. 



Venter with a cross-band of black tomentum on bases of fiftli and follow- 

 ing segments 25. 



25. — Venter with black tomentum on the second and third segments; light col- 

 ored pile and tomentum of abdomen never deep golden-yellow; pile 

 of abdomen mostly erect and bushy; pile of breast, coxae and venter, 

 largely black ; of sides of fifth and sixth segments wholly black ; that 



at tip of last segment also black lib Tacaii;^. 



Venter destitute of black tomentum on second and third segments; light 

 colored pile and tomentum of abdomen deep golden-yellow; the pile 

 mostly depressed and not bushy ; breast, coxse and venter destitute of 



black pile 11a. pretiosa. 



26 — Venter with a cross-band of black tomentum on base of third as well as on 

 bases of fifth and sixth segments; base of wings destitute of an epau- 

 lette of silvery scales in the male; last abdominal segment in the male 

 furnished with silverv scales 10. iniiscaria. 



