NEMATOCERA. 



43 



Discal cell always absent. Head in 

 male dichoptic (eyes separated). 

 Autenniie filiform, the apical part indi- 

 visible into exact joints 



Wing-s with scales. Legs long and 

 slender. Proboscis always long, stiff, 

 conspicuous, formed expressly for 

 biting (except Corethra). Palpi long, 

 stiff, prominent (except Corethra) .... 



Wings with hairs (in some species also 

 Avith small white spots composed of 

 scales*). Legs short and compara- 

 tively stout. Proboscis, without being 

 so long and conspicuous, elongate and 

 horny in Phlehotomus, formed for 

 biting, and in some Psychodin^, 

 though short, capable of piercing the 

 skhi. Palpi short, incurved 



Legs short and stout (about the same as 

 in the Brachycera). Head in male 

 holoptic. i\.ntennae short and com- 

 paratively stout, shorter than thorax . 



Legs normally long and slender (except 

 only in Orphnephila). Head in male 

 dichoptic (except in one or two genera 

 of Mycetophilidje). Antenn;:e long 

 and slender (except in Orphnephila), 

 often longer than the head and thorax 

 taken together 



The 2nd basal cell and the posterior 

 cross-vein present. All veins distinct 

 (BiBiONixiE).t Wings normally broad, 

 costal vein extending round the mar- 

 gin of the wing. Ocelli present. 

 Antennpe short and stout 



The 2nd basal cell always present ; 

 posterior cross-vein always absent. 

 Auxiliary, 1st and 3rd longitudinal 

 veins thickened, the rest generally 

 faint. Wing distinctly broader than 

 usual. Costal vein ending at tip of 

 wing. Ocelli absent. Antennae long, 

 slender, typically nematocerous 



Antennae apparently of three joints, 

 terminating in a bristle. Wing with 

 two basal cells. Legs comparatively 

 short 



AntenuEB normally nematocerous. 

 Wing with only one basal cell (except 

 in one or two genera of Blepharo- 

 CERiD-s:). Legs long- and slender . . 



Dixidae, n. 257. 



Culicidae. 



Psychodidae, p. 196. 



Bibionidae, p. 157, 



Simuliidae, p. 182. 



Orphnephilidae 



(not Oriental). 



* In a few species the wing itself is more or less covered with small scales, 

 in addition to or irrespective of such spots. 



t When the 2nd basal cell and the posterior cross-vein are absent, the 

 longitudinal veins are always very indistinct (ScATorsiNiE). 



