The Curejant Fruit Fly. 



191 



the oviduct and oviductus communis expel the egg into the ovi- 

 positor, a peristaltic movement of the abdominal segments 

 occurs. The egg can be seen gliding through the membrane 

 connecting the tube-like segment with the egg-laying organ and 

 again, when it passes out of the opening near the end of the 

 ovipositor into the egg receptacle. The ovipositor is then with- 

 drawn, and with the abdomen still bent, the fruit fly walks around 

 on the berry, stops a moment to clean off the egg-laying appa- 

 ratus with the tarsi of the hind legs and then takes flight. 



Time Required in Process of Oviposition. 



The time required to rasp through the epidermis of the 

 currant, the time spent in forming the receptacle and depositing 

 an egg and the total time of the entire process of ovipos't'on of 

 ten specimens, which were captured in the field in the morning 

 and allowed to oviposit in the afternoon, is shown in table 7. 



TABLE 7. 



Time Required in Process of Oviposition. 



Time required to 



Time required to 





rasp through 

 epidermis 



form receptacle 

 and deposit egg 



Total time ol 

 oviposition 



(minutes) 



(minutes) 



(minutes) 



2 



1 



3 



2.5 



1.5 



4 



3.5 



1.5 



5 



4.5 



1.5 



6 



5 



3 



8 



8 



1 



9 



8 



2 



10 



8.5 



3.5 



12 



7.5 



4.5 



12 



11.5 



2.5 



14 



Average 6.1 



2.2 



8.3 



The time required to puncture the epidermis depends upon 

 the toughness of the peel, and the general activity of the insect. 

 One female was unable to rasp through the skin of a hard, green, 

 mountain currant and finally deposited several eggs on the out- 

 side of the berry at the calyx end. On cold, cloudy days the 

 fruit flies are not active and the process of oviposition is rare 

 and often prolonged. Adults near the end of their natural life 

 were frequently observed rasping the epidermis of currants and 



