XIvIII. Family DROSOPHILJD^. 



Face nearly vertical in profile, with oral vibrissae, 

 which are sometimes weak. Front with long bristles, 

 not reaching to the anterior part; postvertical bristles 

 convergent; foremost orbital bristle usually proclinate. 

 Third joint of the antennae oval or rounded, the first two 

 short; arista almost always plumose or strongly pectin- 

 ated, though sometimes the rays may be much reduced 

 in number or, rarely, entirely wanting. Abdomen usu- 

 ally short; more elongate in Curtonotum. Auxiliary vein 

 incomplete or indistinct; an incision in the costa before 

 the termination of the first vein ; first longitudinal vein 

 short, not reaching a third of the length of the wing; 

 posterior basal cell usually united with the discal cell, 

 though sometimes complete ; anal cell usually present, 

 but sometimes indistinct or entirely wanting; posterior 

 cross- vein absent in Astcia. 



The species of this family are almost always small, sel- 

 dom exceeding a length of five or six millimeters and 

 usually from one to three; of rather a plump appearance, 

 giving a feeling of coldness to the fingers when grasped. 

 The bristles of the front are usually conspicuous, but the 

 body is without hair. The flies are often caught with 

 the beat-net, and some species are especially abundant 

 about decomposing or fermenting fruit, cider refuse, wine 

 vats, vinegar, etc.; and some are annoying to the house- 

 wife about preserves; even the breath of one who has 

 recently drank wine seems to attract them. 



The great majority of the species the student meets 

 are easily enough located by the absence of the auxiliary 

 vein and second posterior cell together with the plumos- 

 ity of the arista and distinct oral vibrissae. Unfortunate- 



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