[Illustration: FIG. 31.--_Goliathus giganteus_ (Goliath Beetle).]
[Illustration: FIG. 32.--_Anatio ocellata_ (Eyed Ladybird). Europe.]
[Illustration: FIG. 33.--_Endomychus coccineus_. Europe.]
[Illustration: FIG. 34.--_Sagra cyanea_. W. Africa.]
[Illustration: FIG. 35.--_Eumorphus ivguttatus_. Sumatra.]
[Illustration: FIG. 36.--_Lophonocerus barbicornis_. S. America.]
The _Chrysomelidae_, or leaf-beetles (figs. 34, 35), are a very large family, with "tetramerous" tarsi; there seem to be only four segments to the foot, but there are really five, the fourth being greatly reduced. The mandibles are strong, adapted for biting the vegetable substances on which these beetles feed, and the palps of the second maxillae have three segments. Most of the _Chrysomelidae_ are metallic in colour and convex in form; in some the head is concealed beneath the prothorax, and the so-called "tortoise" beetles (_Cassidinae_) have the elytra raised into a prominent median ridge. The most active form of larva found in this family resembles in shape that of a ladybird, tapering towards the tail end, and having the trunk segments protected by small firm sclerites. Such larvae, and also many with soft cuticle and swollen abdomen--those of the notorious "Colorado beetle," for example--feed openly on foliage. Others, with soft, white, cylindrical bodies, which recall the caterpillars of moths, burrow in the leaves or stems of plants. The larvae of the tortoise-beetles have the curious habit of forming an umbrella-like shield out of their own excrement, held in position by the upturned tail-process. The larvae of the beautiful, elongate, metallic _Donaciae_ live in the roots and stems of aquatic plants, obtaining thence both food and air. The larva pierces the vessels of the plant with sharp processes at the hinder end of its body. In this way it is believed that the sub-aqueous cocoon in which the pupal stage is passed becomes filled with air.
The _Cerambycidae_, or longhorn beetles, are recognizable by their slender, elongate feelers, which are never clubbed and rarely serrate. The foot has apparently four segments, as in the _Chrysomelidae_. The beetles are usually elongate and elegant in form, often adorned with bright bands of colour, and some of the tropical species attain a very large size (figs. 36, 37). The feelers are usually longer in the male than in the female, exceeding in some cases by many times the length of the body. The larvae have soft, fleshy bodies, with the head and prothorax large and broad, and the legs very much reduced. They live and feed in the wood of trees. Consequently, beetles of this family are most abundant in forest regions, and reach their highest development in the dense virgin forests of tropical countries, South America being particularly rich in peculiar genera.