THE LITTLE FRUIT FLIES 



(Family Drosophilidce.) 



This group includes the little fruit flies, or pomace flies, so 

 commonly seen about decaying fruit and also about other decaying 

 vegetation. They are frequently found in houses in the autumn 

 about dishes containing pears, peaches and grapes. They are 

 attracted to fruit both for food and as places for oviposition, since 



Fig. 107.— Diosopliila a.nixlophila : a, lai\a; b, pupa; <r, adult. 



their larvs live in decaying' vegetable matter. They are also 

 called "vinegar flies," from the fact that their white, slender 

 larvae are frequently found in canned fruits and pickles which 

 have been imperfectly sealed, occurring mostly near the top of 

 the jars, but living without inconvenience in the briny or vinegary 

 liquid, and transforming within brown puparia around the edges 



of the jar. 



Drosophila ampelophila seems to be the commonest species 

 all over the United States, and is mainly responsible for the injury 

 to canned fruits and pickles. Drosophilas are found comn-o.uy 



185 



