AFFECTION OF INSECTS FOR THEIR YOUNG. 299 



and bore a hole of the requisite depth in very hard substances 

 without ever being displaced. ^ 



The construction of the sting or ovipositor with which the 

 different species of Ichneumon are provided, is not less nicely 

 adapted to its various purposes. In those which lay their 

 eggs in the bodies of caterpillars that feed exposed on the 

 leaves of plants it is short, often in very large species not the 

 eighth of an inch long : having free access to their victims, a 

 longer sting would have been useless. But a considerable 

 number oviposit in larva? which lie concealed where so short 

 an instrument could not possibly approach them. In these, 

 therefore, the sting is proportion ably elongated, so much so 

 that in some small species it is three or four times the length 

 of the body. Thus in Pimpla Manifestator, whose economy 

 has been so pleasingly illustrated by Mr. Marsham^, and 

 which attacks the larva of a wild bee (^Chelostoma^ maxillosa) 

 lying at the bottom of deep holes in old wood, the sting is 

 nearly two inches long : and it is not much shorter in the 

 more minute /. Strobilellce L., which lays its eggs in larva? 

 concealed in the interior of fir cones, which without such an 

 apparatus it would never be able to reach. 



The tail of the females of many moths whose eggs require 

 to be protected from too severe a cold and too strong a lights 

 is furnished, evidently for application to this very purpose, 

 with a thick tuft of hair. But how shall the moth detach 

 this non-conducting material and arrange it upon her eggs ? 

 Her ovipositor is provided at the end with an instrument re- 

 sembling a pair of pincers, which for this purpose are as good 

 as hands. With these, having previously deposited her eggs 

 upon a leaf, she pulls oiF her tuft of hairs, with which she so 

 closely envelops them as elfectually to preserve them of the 

 required temperature, and having performed this last duty 

 to her progeny she expires. 



1 Dr. Burmeister and M. Doyere consider the central piece of the borer of 

 the Cicada as the really piercing organ, and the lateral files as only serving as a 

 point of support ; but Mr. Westwood states that numerous dissections of these 

 parts have convinced him of the correctness of Reaumur's description, that the 

 lateral serrated pieces are the real organs of perforation. (Mod. C'assif. of Ins. 

 ii.424.) 



2 Litm. Trans, iii. 23. 3 Jpis**, c. 2, 7. K. 



