266 HOUSEHOLD INSECTS 



within or about the apple. It does not go into the ground 

 like the larva of the apple maggot. The pupal stage lasts 

 three to five days also, and the adult fly is ready to de- 

 posit eggs within two or three days. Thus a single genera- 

 tion of these fruit-flies may be produced in eleven days. 

 The larvae of the fruit-flies are some- 

 times injurious to grapes on the vines. 

 W. L. Devereau of Clyde, New York, found 

 that these maggots completely ate out 

 the insides of grapes first injured by being 

 pecked by birds while still hanging on the 

 vines. Moreover, the maggots actually 

 bore from one grape to another. Forbes 

 relates the same habit of the larvae at 

 Moline, Illinois. He says they attack 

 most frequently the grapes that have been 

 injured by birds or rot, and after once 

 having begun on a cluster they bore from 

 one grape to another, while the adults are 

 FIG. 85. Pupa constantly depositing more eggs, thus 

 ^iied Uit " fly> fina % destroying all of the berries in a 



cluster. 



The maggots not only attack decaying fruit, but they 

 are often found in canned and pickled fruits. Bowles 

 says that he found the maggots in an earthen jar that had 

 been nearly filled with raspberries and vinegar prepared 

 for the purpose of making raspberry vinegar. On open- 

 ing the jar ten days afterward it was found swarming 

 with the larvae and pupae of the fruit-fly. Hundreds of 

 the maggots were crawling about on the under side of the 

 cover and on the sides of the jar. He further states that 

 he has seen the flies hovering about the corks of wine jars, 



