DEVELOPMENT OF PARACOPIDOSOMOPSIS 6 



found on various Cruciferae throughout the summer months, 

 but the mam generation appears about the 1st of October, when 

 the fall crop of cabbage is a month or six weeks old. There is 

 of course a considerable overlapping of generations. From Octo- 

 ber 1st until late in December I have been able to rear two com- 

 plete generations of the parasite in the laboratory. October and 

 November are therefore the best months in which to collect 

 material. 



The parasite will deposit its eggs at any time during the em- 

 bryonic period of the host, which lasts from seventy to eighty 

 hours. After the young caterpillar hatches, the parasite will 

 no longer parasitize it. There are many interesting points in 

 the behavior of these insects, especially in connection with egg 

 laying. They are positively hehotropic and move with great 

 rapidity toward the light, which fact makes it easy to handle 

 them in the laboratory. 



The individuals in one carcass all emerge at about the same 

 time, and the females whether fertihzed or not are ready to lay. 

 If males are present, they at once mate with the females. One 

 male will mate with several females. If a single female be 

 introduced into a vessel containing a brood of males, which 

 have become quiet, the entire blood immediately becomes active. 



In crawling over the surface of the table or leaf, the parasite 

 feels its way along by means of the antennae. This is the method 

 used by the female to find the host egg on the leaves of the cab- 

 bage. Once an egg is located, the female examines its surface 

 by the tips of the antennae, which vibrate with great rapidity. 

 If the egg happens to belong to an insect other than the Auto- 

 graphra moth, the female leaves it in a little while and continues 

 her search for the desired egg. 



In preparing for oviposit ion the female mounts the egg and 

 clasps it with the second and third pau's of legs. The first pair 

 of legs are either held free or placed on the surface of the leaf. 

 The tip of the abdomen is then bent down until it comes in 

 contact with the egg. She then braces herself and forces the 

 ovipositor into the egg. During the act of lajdng, the female 

 remains perfectly motionless, with the head and antennae bent 



