CLASSIFICATION AND DESCRIPTION OF COMMON INSECTS 24 1 



BB. With rudimentary mouth-parts; palpi wanting; antennae with dorsal 

 arista.— tE^^r/^o" (Bot Flies), p. 254. 

 BBB. With well developed mouth-parts; palpi present; head with a suture 

 above the antennae. — Superfamily Muscoidea. 

 C. Alulets small; eyes of males not contiguous; thorax without com- 

 plete transverse suture. — (Acalyptrate Muscids.) 



Rli. 



Miti 



Fig. 149. — Venation of a leptid (Leptis). 

 {After Comstock.) 



Fig. 150. — Venation of a syrphid 

 (Eris talis). (After Comstock.) 



D. Subcostal or auxiliary vein ending in the costa and distinctly 



separate from Radius I, or first longitudinal, which usually 



ends near the middle of the wing. Anal cell present. 



E. Oral vibrissae present; front bristly; R. nearly half the 



wing length; cross veins not close together; yellow or 



brown. — Scatophagidce (Dung Flies). 



Fig. 151. — Venation of Thereva. 

 {After Comstock.) 



Fig. 152. — Venation of a muscid 

 {Musca). {After Comstock.) 



EE. Oral vibrissas absent; eyes large; first posterior cell (R5) 

 closed or narrowed in the margin; proboscis and ovi- 

 positor greatly lengthened. — Conopidw (Thick-headed 

 Flies). 

 DD. Subcostal vein absent, vestigial or incomplete; Radius I 

 usually ending in costa before middle of wing. 

 E. Discal and basal cells united; Anal cell absent. — Os- 

 cinidce (Grass Stem Flies), p. 260. 



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