Beetle

Beetle, the name of an order of insects technically known as Coleoptera. There are indeed some insects popularly called 'beetles' which are not Coleoptera, and some Coleoptera which would hardly be termed 'beetles,' but for practical purposes the two words are synonymous. They have generally the usual four wings, but the front pair form hard and horny covers for those behind, which alone are used in flight. The feelers or antennæ have only a few joints; the jaws or mandibles are almost always biting organs like those of the Cockroach (q.v.), and the fourth pair of mouth appendages (second pair of maxillæ) are completely fused together. They go through a complete metamorphosis (q.v.), the young beetles being caterpillar-like forms, usually with six legs, and always unlike the adult. The males are usually distinguishable from the females by differences of size, form, colour, fighting organs, sounds, &c. For general anatomy, see INSECT. There are probably about 100,000 different species, more than twice the total number of backboned animals, and among these myriads there is, within a small range, such a marvellous diversity of form, colour, size, and habit, that general characteristics are hard to note. About the beginning of this century, Latreille divided this vast multitude into four great groups according to the number of small joints in the lowest part of the leg. But his four divisions (Pentamera, Heteromera, Tetramera, and Trimera) are artificial, and are abandoned by many modern coleopterists, who arrange the host in seventy-five families. It may be said of most beetles that they are strong, voracious insects, acting as 'universal scavengers,' preferring to remain concealed during the day, and only on occasions taking to flight. Their food varies greatly from hard wood to soft fruits, from the carcasses of animals to dung, and a few become parasites. They are found in water and on land, on plants and among stones, burrowing in the ground and drilling holes in wood, in fact in almost every variety of habitat. Fossil-beetles begin to appear in the carboniferous strata, and are often found imbedded in amber. Their practical importance in regard to vegetation, and their numerous interesting peculiarities of form and habit, will be discussed under special articles.

See the following articles on various beetles: