PARASITES THAT ARE FREE WHEN OLD. 163 



them which are richly endowed, and one would never 

 imagine that they would have recourse to strangers in 

 order to bring up their progeny. All their young family 

 is usually entrusted to the care of a nurse, who lives 

 just long enough to bring them up ; she gives them con- 

 venient shelter under her roof, and often bestows upon 

 them the last drop of her blood. 



When the young one has at last abandoned her first 

 resting-place, she begins to think seriously of Hymen ; 

 she changes her dress and her mode of life, and seeks 

 no more extraneous assistance till she lays her eggs. 

 Among the animals brought up in this manner, the most 

 remarkable are the Ichneumons, which have always 

 attracted the notice of entomologists. These charming 

 creatures, whose shape is delicately slender, whose trans- 

 parent wings flutter with so much grace, have a less 

 stormy youth than their boldness would induce us to 

 suppose. As the cuckoo lays her eggs in the nest of a 

 strange bird, the mother ichneumon deposits hers in a 

 caterpillar full of health, by means of a long and 

 thread-like ovipositor, so that the larvae as soon as they 

 are hatched, find themselves in a bath of blood and 

 viscera, which serves them for food. The different 

 organs palpitate under the teeth of these intruders, and 

 the young larva grows and increases in size till it is 

 hatched under the skin of its nurse : this skin is the 

 cradle of the ichneumon. 



The young ichneumon devours its nurse piecemeal, 

 organ after organ ; and for fear that death should super- 

 vene too quickly, the mother takes care to chloroform 

 the victim beforehand to make her last longer. The 

 method which many of them adopt to get rid of their 



