SOUTH AFRICAN BAGWORMS. 183 



entire length would make it necessary for the larva to leave 

 its bag — a procedure which would be highly dangerous, 

 and almost impossible. The older and smaller twigs are 

 probably removed as the larva grows and are replaced by 

 larger ones, as it is noticed that the mature bags contain 

 none of the small, thin sticks which form the bao-s of the 

 younger larvae. 



The sticks are approximately of equal length, but in the 

 bags of the mature larvae we find usually one or two of the 

 sticks longer than the others and projecting beyond the 

 lower end of the bag. Fuller claimed that these longer 

 sticks were probably for the male moth to alight on, to 

 facilitate copulation, while the Rev. Junod supposes that 

 they would be a protection for the female when she exposes 

 the anterior part of her body, preventing her from falling 

 out. Neither of these explanations appear to be correct. If 

 Fuller were right in his supposition, then these projecting 

 sticks would be found mostly or exclusively on the female 

 bags ; but we found that the male bags invariably present 

 these longer sticks, while on the female bags they are very 

 often absent. Also, the twigs are too far away from the 

 centre of the bag to allow a male, alighting on them, to 

 insert its abdomen through the neck of the bag for copula- 

 tion. Against the Rev. Junod's proposition we must mention 

 that those sticks which may be present on the female bags 

 are also too far away from the centre to be of any assistance 

 to the female. As a matter of fact we found a great many 

 females dropping out of their bags when the males were 

 tardy in their appearance or were prevented from getting 

 access to the females. 



We have observed that these projecting sticks are made 

 use of in the emergence of the male moth. The male pupa 

 works itself more than half-way out of the bag, and the 

 moth, emerging, endeavours to grasp one of them with its 

 legs, and is thereby given a purchase to withdraw its abdo- 

 men from the pupa-case. It then rests on the twig while 

 its wings are expanding and hardening. 



