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 transparent 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 larvæ 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 supervene 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 young, reminds 164 us forcibly of the turning-box in which they used formerly to place children whom they wished to be brought up by public charity; with this difference, that young ichneumons are not only fed and taken care of by some good neighbour, but that her body itself serves them as food. It has sometimes happened that entomologists, instead of finding beautiful butterflies produced from the caterpillars which they had reared, have had nothing hatched but a brood of ichneumons. Was it not natural then for them to dream of the transformation of species, when they saw issuing from the skin of a caterpillar, which is usually transformed into a beautiful chrysalis, a swarm of small winged flies which disperse with the rapidity of lightning? These ichneumons discover with astonishing ingenuity the caterpillar which can bring up their young, and they often reach it with their ovipositor in the midst of a fruit, or in the substance of a branch of a tree. Every one knows the _Anobium_ and other little beetles which attack wood, and live in the dark galleries which they excavate. The mother ichneumon knows perfectly how to discover the beetle which bores into our furniture, and winged ichneumons have often been seen to proceed from worm-eaten wood. It is not only caterpillars that are sought by ichneumons for the sake of their young; many kinds of larvæ of coleoptera and hemiptera, of aphides and weevils, are attacked by the mother ichneumons, which plunge their ovipositors between their articulations. These winged corsairs well know the weak points of their cuirass.