FAMILY BOMBYLIID.E THE BEE FLEES 195 



15. Face acute, strongly projecting Chrysanthrax Osten Sacken 



Face not strongly projecting, the oral margin rounded (28). 



Thyridanthrax Osten Sacken 



16. Proboscis projecting far beyond the anterior oral margin 17 



Proboscis projecting but little beyond the oral margin 18 



17. Abdomen with broad scales on basal half (27). 



* Lepidanthrax Osten Sacken 

 Abdomen without broad scales on basal half Rhynchanthrax Painter 



18. Face conical, acute at oral margin Paravilla Painter 



Face obtuse below, the oral margin x-ounded Villa Lioy 



1 9. With four posterior cells 24 



With only three posterior cells 20 



20. Slender, elongate species, with long, slender legs 21 



Shorter, more thick-set species, the abdomen tapering apically 22 



21. Abdomen enlarged apically; eyes holoptic (23, 24) . . .Systropus Wiedemann 

 Abdomen not enlai-ged apically, cylindrical; males only holoptic. 



Dolichomyia Wiedemann 



22. Three submarginal cells or the third antennal segment obtuse 23 



But two submarginal cells; third antennal segment acute (18, 19, 20, 29). 



fGeron Meigen 



23. Body clothed mostly with scales, the thorax with bristles; abdomen 



decumbent; antennae long (21, 22) Toxophora Meigen 



Body clothed chiefly with hair; abdomen not decumbent (41, 66). 



Rhabdopselaphus Bigot 



24. Apical (first posterior) cell open or closed in the wing margin 31 



Apical cell closed before the margin of the wing and petiolate 25 



25. Two submarginal cells 27 



Three submarginal cells 26 



26. Head broader than the thorax; posterior orbits not excised (10, 11). 



Pantarbes Osten Sacken 

 Head narrower than the thorax; posterior orbits excised. . .Triplasius Loew 



27. Proboscis protruding far beyond the anterior oral margin 28 



Proboscis not protruding beyond the oral margin. . . .Anisotamia Macquart 



28. First basal cell much longer than the second 29 



First basal cell not longer than the second 30 



29. Posterior orbits of the eyes convex or only slightly emarginate in 



the middle; head small (9, 63) Bombylius Linnaeus 



Posterior orbits broadly and deeply emarginate; head as wide as the 

 thorax JHeterostylum Macquart 



30. Shape of the face concealed by dense hair; vein closing the discal cell 



anteriorly half as long as the ultimate section of the vein behind it. 



Anastoechus Osten Sacken 

 Shape of the face plainly visible; vein closing the discal cell anteriorly 

 not nearly half as long as the ultimate section of the vein behind it 

 (12) Systoechus Lcew 



* Curran, 1930, Amer. Mus. Novit. No. 409. p. 1. 

 t Painter, 1932, Tr. Amer. Ent. Soc, Iviii, pp. 139-167. 

 t Painter, 1930, J. Kans. Ent. Soc, iii, p. 1. 



