THE REAE1NG OF CATERPILLARS 



85 



to say, the ichneumon-flies, which lay their eggs inside the cater- 

 pillars, with the result that the grubs which hatch out so weaken 

 their host that it has not strength to become a butterfly or moth, even 

 if it is able to turn into a chrysalis. Where the body of the caterpillar 

 is pierced, a mark remains, and upon that 

 of the lobster caterpillar there is a spot 

 naturally produced which will deceive the 

 ichneumon-fly into believing that her prey 

 has already suffered from the attentions of 

 one of her kind, and she straightway de- 

 parts leaving it unmolested. Other British 

 caterpillars, such as those of the elephant- 

 hawk moths and the puss moth, have peculiar 

 devices which the young student may well 

 discover for himself, and he may advan- 

 tageously seek an explanation of the 

 brilliant and conspicuous coloration of some 

 caterpillars (and indeed of other animals), 

 which instead of obscuring them, forces their 

 presence upon one's notice. Beautiful as 

 caterpillars may be, they are far surpassed by 

 many butterflies, and one of us has suggested 

 that they might be reared like flowers * very 

 generally are, merely for their appearance. For the purpose of keeping, 

 say, the beautiful swallow-tail butterfly, a large flight cage should be 

 made of mosquito netting, preferably protected by a small glass-house 

 built over the ground in which carrots (the food plant of the larvae) 

 in a flowering condition are growing. If a large number of insects 



* "A Caterpillar Farm." By Wilfred Mark Webb, F.L.S. Royal Magazine, Vol. VII 

 (1902), page 531. 



Photograph by Alban W. Duffiehl. 



FIGURE 203. A white Butterfly. 



