Caterpillars also exhibit a considerable amount of detailed resemblance to the plants on which they live. Grass-feeders are striped longitudinally, while those on ordinary leaves are always striped obliquely. Some very beautiful protective resemblances are shown among the caterpillars figured in Smith and Abbott's _Lepidopterous Insects of Georgia_, a work published in the early part of the century, before any theories of protection were started. The plates in this work are most beautifully executed from drawings made by Mr. Abbott, representing the insects, in every case, on the plants which they frequented, and no reference is made in the descriptions to the remarkable protective details which appear upon the plates. We have, first, the larva of Sphinx fuciformis feeding on a plant with linear grass-like leaves and small blue flowers; and we find the insect of the same green as the leaves, striped longitudinally in accordance with the linear leaves, and with the head blue corresponding both in size and colour with the flowers. Another species (Sphinx tersa) is represented feeding on a plant with small red flowers situated in the axils of the leaves; and the larva has a row of seven red spots, unequal in size, and corresponding very closely with the colour and size of the flowers. Two other figures of sphinx larvae are very curious. That of Sphinx pampinatrix feeds on a wild vine (Vitis indivisa), having green tendrils, and in this species the curved horn on the tail is green, and closely imitates in its curve the tip of the tendril. But in another species (Sphinx cranta), which feeds on the fox-grape (Vitis vulpina), the horn is very long and red, corresponding with the long red-tipped tendrils of the plant. Both these larvae are green with oblique stripes, to harmonise with the veined leaves of the vines; but a figure is also given of the last-named species after it has done feeding, when it is of a decided brown colour and has entirely lost its horn. This is because it then descends to the ground to bury itself, and the green colour and red horn would be conspicuous and dangerous; it therefore loses both at the last moult. Such a change of colour occurs in many species of caterpillars. Sometimes the change is seasonal; and, in those which hibernate with us, the colour of some species, which is brownish in autumn in adaptation to the fading foliage, becomes green in spring to harmonise with the newly-opened leaves at that season.[71]