SOUTH AFRICAN BAGWORMS. 679 



■ave well cajiable of long-sustained flights. Several cases have 

 come under our observation where females have been visited 

 by males which could only have come from a couple of miles 

 distant. Flying only takes place in the bright sunlight and 

 ■during the hottest part of the day, roughly between 10 a.m. 

 and 3 p.m., while if the sun be temporarily obscured by a 

 ■cloud, no males are to be seen. 



Fuller,in his various discussions on the bagworm, mentioned 

 previously, maintains that the males are very weak flyers and 

 can only fly for a short distance. His observations were based 

 on moths bred in the laboratoiy, and under those conditions, 

 in the absence of sun and free air, the moths make no attempt 

 to fly and visit the females, even when the latter are confined 

 in the same breeding cage. 



This strong power of flight, although no longer necessary 

 under the plantation conditions, may well have been advan- 

 tageous, or even essential, under the original environment, 

 namely in the scattered thorn bush, where the species 

 used to breed. Here long distances might have to be 

 ■covered across the veld before a receptive female was found, 

 and in the absence of warning coloration or any other means 

 ■of defence, its only safety from birds would lie in a quick 

 flight. The transparency of its wings (the few hairy scales 

 with which the wings are covered on emergence are shaken 

 off with the first vibrations) also assists in making the moth 

 very inconspicuous in its flight across the open spaces. 



Copulation. — The male, upon finding a female bag, alights 

 at the lower end, and with its wings and antennae (text-fig. 5, H,i) 

 vibrating continuously it endeavours to introduce its abdomen 

 through the neck of the bag. This is usually accomplished 

 in a few minutes, the neck of the bag being partly invaginated 

 in the process. Now with a series of efforts the abdomen is 

 fully stretched so as to reach the female. The normal length 

 of the abdomen of the male is about 5 mm., but after full 

 extension it reaches a total length of 20 mm., at which point 

 the intersegmental membranes are stretched to their fullest 

 extent and apparently the limit is reached. But even this 



VOL. 3, PART 3. 45 



