288 AFFECTION OF INSECTS FOR THEIR YOUNG. 



posed to the attacks of one or other of them ; and even the 

 pupee, nay the very eggs of these animals, are not safe from 

 their insidious manoeuvres. The size of the different species 

 varies in proportion to that of the bodies which are to be their 

 food ; some being so inconceivably small that the egg of a 

 butterfly not bigger than a pin's head is of sufficient magni- 

 tude to nourish two of them to maturity ' ; others so large, 

 that the body of a full-grown caterpillar is not more than 

 enough for one. They are the larvas of these Ichneumons 

 which make such havoc of our pigmy tribes: the perfect 

 insect is a four-winged fly, which takes no other food than a 

 little honey ; and the great object of the female is to discover 

 a proper nidus for her eggs. In search of this she is in con- 

 stant motion. Is the caterpillar of a butterfly or moth the 

 appropriate food for her young ? You see her alight upon 

 the plants where they are most usually to be met with, run 

 quickly over them, carefully examining every leaf, and, 

 having found the unfortunate object of her search, insert her 

 sting into its flesh and there deposit an egg. In vain her 

 victim, as if conscious of its fate, writhes its body, spits out an 

 acid fluid, menaces with its tentacula, or brings into action 

 the other organs of defence with which it is provided. The 

 active Ichneumon braves every danger, and does not desist 

 until her courage and address have insured subsistence for 

 one of her future progeny. Perhaps, however, she discovers, 

 by a sense the existence of which we perceive, though we 

 have no conception of its nature, that she has been forestalled 

 by some precursor of her own tribe, that has already buried 

 an egg in the caterpillar she is examining. In this case she 

 leaves it, aware that it would not suffice for the support of 

 two, and proceeds in search of some other yet unoccupied. 

 The process is of course varied in the case of those minute 

 species of which several, sometimes as many as 150, can 

 subsist in a single caterpillar. The little Ichneumon then 

 repeats her operations, until she has darted into her victim 

 the requisite number of eggs. 



The larvae hatched from the eggs thus ingeniously de- 

 posited, find a delicious banquet in the body of the caterpillar, 



1 Bonnet, ii. 344. 



