60 NORTH AMERICAN DIPTERA. 



is. APIOCERIM;. 



Rather large, elongate, chaetophorous, thinly pilose flies. 

 Antennae with a simple, short style. Front not excavated, 

 broader in the female. Ocelli present. Face short. Probos- 

 cis with pseudo-tracheate labella. Third longitudinal vein of 

 the wing usually furcate ; basal cells large ; five posterior cells 

 present. Empodia wanting. Male forceps enlarged. 



Less than a dozen species of this family are known through- 

 out the world, six of which have been described from North 

 America. The flies have much the appearance of large The- 

 revids or Asilids, from which they will be at once distinguish- 

 ed by the anterior curvature of the outer veins of the wings. 

 The larvae are wholly unknown. For a discussion of the rela- 

 tionships of the family, as also a bibliographical list, see 

 Kansas University Quarterly i, 101. 



TABLE OF GENERA. 



1. Palpi two-jointed, large; the second vein from the discal vein termi- 



nates beyond the tip of the wing. . . APIOCERA Westwood. 



Pa4pi one-jointed, small; the second vein from the discal cell terminates 



before the tip of the wing. . . ... . . 2 



2. Anal cell closed RHAPHOMIDAS Osten Sacken. 



Anal cell open. APOMIDAS Ooquillett. 



19. NEMISTRINID^S. 



Species of moderate size, not elongate, thinly or densely 

 pilose. Neuration complicated, the fourth and fifth veins are 

 curved forward to terminate before the tip of the wing, the 

 anterior cross-vein is obsolete, that is the third and fourth 

 veins coalesce for a short distance ; basal cells long. Antennae 

 small, short; third joint simple, with a terminal, slender, 

 jointed style. Proboscis sometimes elongate. Ovipositor of 

 the female elongate, often slender. Tibiae without spurs ; 



