TABLE OF FAISIILIES 23 



31. Two or more submarginal cells, the third vein furcate 32 



Only one submarginal cell, the third vein simple 38 



32. Front hollowed between the eyes, strongly concave from anterior view.. 33 

 Front scarcely or not at all concave from anterior view 34 



33. At most one ocellus; at most two veins reach the wing margin behind 



the apex (p. 163) MYDAID^ 



Three ocelli; at least four veins reach the wing margin, or extend to- 

 ward it, behind the apex (p. 167) ASILID^ 



34. Costa continuing around the wing; fourth vein ending beyond the wing- 



tip 35 



Costa not continued beyond the apex of the wing; fourth vein ending 

 before the wing-tip (p. 161) SCENOPINID^ 



35. Five posterior cells 36 



At most four posterior cells 37 



36. Fourth vein ending before the apex of the wing. .(p. 189) APIOCERIDiE 

 Fourth vein ending behind the apex of the wing. . . (p. 185) THEREVID^ 



37. Anal cell open or closed near the wing margin, the anal vein reaching 



the margin (p. 191) BOMBYLIID^ 



Anal cell closed far from the wing margin, the anal vein never extend- 

 ing to the margin, sometimes absent (p. 205) EMPIDi35 



38. Anal cell elongate, tapering and acute apically, closed near the border 



of the wing; basal cells usually elongate 39 



Anal cell short, transverse, oblique, or convex apically, if somewhat 

 pointed the apex partly transverse, partly di"awn ovit into a triangular 

 point posteriorly 40 



39. Anal cell closed very close to the wing margin; a spurious vein running 



obliquely between the third and fourth longitudinal veins. 



(p. 247) SYRPHIDJE 

 Anal cell usually shorter; no spurious vein 40 



40. Head extremelv large, hemispherical, the front and face very narrow; 



arista dorsal' (p. 245) PIPUNCULID^ 



Head not unusually large; face or front usually wide 41 



41. Frontal lunule entirely absent, the parafacials not differentiated by a 



suture 42 



Frontal lunule present; parafacials differentiated by a suture which ex- 

 tends above the antennae and is indistinct only in some Conopidse. . . .44 



42. Anterior crossvein situated at or before the basal fourth of the wing; 



second basal and discal cells always united... (p. 215) DOLICHOPID/E 

 Anterior crossvein situated far beyond the basal fourth of the wing or 

 the second basal cell complete 43 



43. Anal cell pointed posteriorly; proboscis never rigid and adapted for 



piercing ' (p. 242) PLATYPEZID^ 



Anal cell not pointed posteriorly; proboscis usually rigid; never a single 

 row of acrostical hairs (p. 205) ExMPID^ 



44. Cox£e close together at the base, the legs attached ventrally 45 



Coxas widely separated at the base, the legs attached toward the sides 



of the thorax; usually leathery or coriaceous flies; ectoparasites 

 (Pupipara) 91 



