215 



IT. The contact of the discal cell with the third posterior not much 

 longer than its contact with the fourth posterior; proboscis long; 

 sides of the abdomen with a fringe of scales and not with hairs 



only. . Lepidanthrax. 



The contact of the discal cell with the third posterior at least twice 

 as long as its contact with the fourth posterior; the latter con- 

 tact often merely punctiform (1, 6) . . . . Anthrax. 



12. Wings with three posterior cells. ...... 39 



Wings with four posterior cells. ...... 13 



13. First posterior cell closed, or at most very narrowly open (Para- 



bombylius] . ......... 14 



First posterior cell open. ....... 21 



14. Three submarginal cells. . . . . . . . 15 



Two submarginal cells. . . . . . . . . 16 



15. Head broader than thorax; posterior orbits not excised (1O, 11). 



Pantarbes. 

 Head narrower than thorax, posterior orbits excised. 



Triplasius. 



16. First basal cell longer than the second. .... 17 

 First basal cell not longer than the second; the anterior cross-vein 



situated near the base of discal cell. ..... 20 



17. Proboscis very short, not protruding beyond oral margin; anal 



cell usually closed; frontal triangle of male large, the eyes nar- 

 rowly contiguous; large species (Anisotamia) . Oncodocera. 

 Proboscis more or less elongate; anal cell usually open. . 18 



18. First posterior cell closed at some distance from the border of the 



wing. ........... 19 



First posterior cell narrowed, or closed in or near the border of the 

 wing; front with a silvery spot on each side below; rather small 

 species (5-8 mm) Parabombylius.* 



19. Head comparatively small; the emargination of the occipital orbits 



almost imperceptible (fig. 84, 9). . . . Bombylius. 

 Head broad; emargination of the occipital orbits distinct. 



Heterostylum. 



20. Face thickly clothed with pile. . . . Anastcechus. 

 Face sparsely clothed with pile (12) . . . Systoschus. 



* Bombylius ater, syndesmus, albopemcillatus, dolorosns. 



