CATERPILLAR, the name given to the larvae of lepidopterous insects—butterflies, moths, and hawk-moths. Caterpillars exhibit as great differences as subsist among the perfect insects into which they change, and the family, genus, and species may be deter mined by the characters of the C., as well as of the perfect insect. Their body is gen erally long, nearly cylindrical, soft, and consisting of 12 rings or segments besides the head, with nine spiracles or small openings for respiration on each side. The head is much harder than the rest of the body, of a sort of almost horny substance, P.m] has 6 small shining points on each side, which are rogarded as simple or stemma tie eyes, and is also furnished with two very short rudimentary antennte. The mouth is adapted for tearing, cutting, and masticating the substances on which the 0. is destined to feed, which are very various in the different species, although in all extremely different from the food of the perfect insect; it is provided with two strong mandibles, or upper jaws: two nio.rake, or lower jaws; a labium, or lower Hp; and four pulpi, or feelers. In the mouth also is situated the spineret of those species which, when they change into the chrysalis or pupa state, envelop themselves in silken cocoons. See SILK-WORNL The first three segments of the body are each furnished with a pair of feet, which are hard and scaly, and represent the 6 feet of the perfect insect; some of the remaining segments are also furnished with feet, varying in all from 4 to 10 in number, the last pair situated at the posterior extremity of the body; but these feet are soft and membranous or fleshy, and armed at their extremity with a sort of circlet of minute hooks. All the feet or legs are very short. Those caterpillars in which the as they are sometimes called, or supplementary soft feet, are pretty equally distributed along the body, move by a sort of regular crawling motion; but those which have only four such feet situated near the posterior extremity move by alternately taking hold by what may be called their fore feet and their hind-feet, now stretching the body out to its full length, and now bending it into an arch, whilst the hinder part is brought forward almost into contact with the forepart. Caterpillars which move to this way are called geometers or loopers. Some cater
pillars have the power of fixing themselves by the two hind feet to a twin. and stretching P' themselves out as straight as a rod, so that being in color very like a twig of the tree on the leaves of which they feed, they are not readily observed. The muscular power required for this position of rest is very great, and Lyonnet found the number of mus cles in a C. to be more than 4,000. The skin of some caterpillars is naked, that of others is covered with hairs, spines, or tubercles. Some make for themselves nests or tents of silk, under which they dwell in societies, protected from the inclemency of the weather. Many construct cases or sheaths by agglutinating various substances together, as the C. of the common clothes-moth. Some roll together leaves, and fix them by threads„ so formiug a dwelling for themselves; and a few burrow and excavate galleries in the substance of leaves. Many feed on leaves; many being limited to a particular kind of plant, or to a few nearly allied plants. Some feed on flowers, some on seeds, some on roots, and some even on the woody portions of stems; some on wool, hides, furs, and other animal substances; a few on lard, and other kinds of fat. Among the admirable arrangements which make all nature harmonious, is the adjustment of the time of each kind of C.'s appearance to that of the leaf or flower on which it is to feed.