“Every larva is a gluttonous eater, because it must grow big and accumulate the wherewithal for its subsequent changes of form. Nor are caterpillars lacking in response to this serious duty. The future butterfly’s welfare is at stake. Made solely for eating, the larvæ gnaw and browse unceasingly. Each one has its own particular kind of sustenance, its chosen plant, and nothing else meets the requirements. The larva of the Vanessa selects the nettle and turns with aversion from all substitutes; that of the Pieris, a white butterfly with black spots, will have only the cabbage; that of the Machaon, a butterfly with large wings that end in a sort of tail, feasts on fennel; and so of others.
“After attaining the full size assigned to them by nature, caterpillars, like other larvæ, prepare for their transformation. Some shut themselves up in a cocoon made from a silken thread that they spin from their mouth, while others content themselves with binding together, by means of the small supply of thread at their disposal, particles of earth, bits of wood, and hairs plucked from their own body. Thus is obtained, at small expense, a sufficiently substantial temporary abode. Finally, still others, especially among the butterflies that fly in the daytime, merely seek a retreat on the side of some wall or against a tree-trunk, and there suspend themselves in a girdle of silk. [[255]]
“These precautions taken, the caterpillar strips off its skin and becomes a nymph, but very different from that which the stag-beetle showed us. The coleopter, in its nymph stage, was already recognizable, with its branching mandibles, its legs folded on its stomach, and its wings enclosed in their sheaths. The butterfly, on the contrary, is not at all discernible under the casing of the nymph. This nymph, with skin as tough as parchment, is an object little indicative of its true nature and much more suggestive of the kernel of some strange fruit than of any animal form. Because of its shape, so different from that shown to us by ordinary nymphs, it has received a special name, that of chrysalis.
“This word means golden sheath. Sometimes, notably in the case of the Vanessa, the chrysalis is adorned with gilding; but in the great majority of instances the suggestive name is not deserved, a uniform chestnut hue, darker or lighter, being the usual color of the chrysalis. Ripened by long repose, this species of animal shell splits down the back and releases the perfect insect, complete in all its attributes. The butterfly passes a few festive days amid the flowers, and before dying lays eggs whence will spring caterpillars to continue the race.” [[256]]
[1] The author does not, either here or later, distinguish by name, as might have been done, between butterflies and moths. The latter fly mostly in the evening or at night.—Translator. [↑]
CHAPTER XLIX
ANTS
“Ants live in communities, each containing many members, in underground abodes, where the young are reared. These communities are composed of three kinds of insects: males and females, recognizable by their large transparent wings, four to each ant; and the neuters, or workers, which have no wings. These last, the workers, build the house, take care of the community, rear the larvæ and bring them their food, distributing it to each one. The others do not work. To add to the population by furnishing an abundant supply of eggs is all that they are expected to do.