The True Flies 



Style of antennae, when present, much narrower than the 

 third antennal joint, fourth vein ending below the wing 

 tip Family Bombyliidce. 



24 — Discal cell wanting or coalescing with one of the other cells, 

 fourth vein coalescing with the fifth for a considerable 

 distance, or the wings having two longitudinal and 

 three or four oblique veins issuing from the second 

 (Super-family Phoroidea) 29 



Discal cell usually present, fourth vein not coalescing with 

 the fifth, wings provided with more than two longi- 

 tudinal veins (Super-family Asiloidea) 25 



Super-family ASILOIDEA Coq. 



25— Apex of the third vein usually situated below the extreme tip 

 of the wing, body sometimes metallic green or bluish : 26 



Apex of the third vein situated at or above the tip of the 

 wing, body never metallic green or bluish, proboscis 

 furnished with terminal lips, anal cell much longer than 

 the second basal, three posterior ceils present, third 

 vein forked, antennae not furnished with a style or arista 

 Family Scenopinidce. 



26 — With five posterior cells in each wing, anal cell always 

 present and much longer than the second basal, third 

 vein always forked .' 27 



With less than five posterior cells, anal cell sometimes want- 

 ing; when present it is shorter or only slightly longer 

 than the second basal cell 28 



27 — Proboscis furnished with terminal lips, face strongly retreat- 

 ing on its lower part, not bristly .... Family Therevidce. 



Proboscis sharp-pointed, not provided with terminal lips, 

 face projecting forward or convex on its lower part, 



provided with strong bristles or long hairs 



Family Asilidce. 



28 — Second basal cell, when confluent with the discal, the color 

 of the body is never metallic green, anal cell sometimes 

 wanting, third vein sometimes forked. .Family Empidce. 



Second basal cell confluent with the discal, anal cell always 

 present, third vein never forked, color of body usually 



metallic green Family Dolichopodidce. 



88 



