Drosophilidae 43 7 



room varying from 75 to 8o° F.; humidity 60-70%; food, yeast 1 

 part, honey 4 parts; light, daylight from a north window. 



Pre-oviposition period 7 to 10 days 



Oviposition period (average) 71 days 



Pre-mating 4 to 10 days 



Mating period (average) 52 days 



Larval emergence from apples 



Time to first emergence* (average) 21 days 



Period of emergence (average) 12 days 



Fly emergence from soil 



Time to first emergence* (average) 63 days 



Period of emergence (average) 107 days 



Maximum life of flies 103 days 



Average life 41 days 



Sex ratio of flies bred in laboratory 45% males, 55% females 



Bibliography 

 Fluke, C. L. 1933. J. Econ. Ent. 26:1111. 



Family piophilidae 



J 



PIOPHILA CASEI 



Don C. Mote, Oregon State Agricultural College 



I USED battery jars with some sand in them, and a piece of cured 

 ham as the medium in which the cheese skipper was raised. Cheese- 

 cloth was placed over the top of the battery jar. Once the infestation 

 was started, little or no attention was required, the cheese skippers 

 multiplying continuously for over a year. 



Family drosophilidae 



J 



CULTURE METHODS FOR DROSOPHILA 



A. H. Sturtevant, California Institute of Technology 



THE cultivation of Drosophila in the laboratory is simple, rapid, 

 and may be carried out with little or no special equipment. The 

 technique has been elaborated for special purposes — for quantity pro- 

 duction, for the maintenance of relatively constant conditions, and for 

 the reduction of mortality of weak types — but for many purposes these 

 elaborations remain unnecessary. It is proposed here to describe the 

 simple techniques, together with certain of the more complicated de- 

 velopments. 



♦From date of egg deposition. 



