Page:Encyclopædia Britannica, Ninth Edition, v. 6.djvu/157

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COLEOPTERA 131 distinguished from the other groups of beetles by having the elytra much shorter than the abdomen, although they still suffice to cover the long membranous wings, which when not in use are completely folded beneath. The abdo men is long and exceedingly mobile, and is employed in folding and unfolding the wings. It is furnished at its extremity with two vesicles which can be protruded or withdrawn at pleasure, and from which, when irritated, many species emit a most disagreeable odour, although in a few the scent is more pleasing ; " one species, " says Kirby, " which I once took, smelt precisely like a fine high scanted pear, another like the water-lily, a third like water- cresses, and a fourth like saffron." They are very voracious both in the larval and perfect states, feeding chiefly upon decaying animal and vegetable matters, although a few species devour living prey. Many of the smaller forms reside in and feed on mushrooms, some are found abundantly under putrescent plants, others in manure heaps, where they feed upon the maggots of flies, while there are a few forms which make their homes in the nests of the hornet and the ant. The larvae bear a con siderable resemblance to their parents in form and habits, and have the terminal segment of the abdomen prolonged into a tube with two conical and hairy appendages attached. The Brachelytroua beetles form an extensive group, almost entirely confined to the temperate regions of the northern hemisphere, Great Britain alone possessing nearly 800 species. They ara familiarly known in this country as Cock-tails, one of the largest and most familiar species being that known as the Devil s Coach- horse (Goer ins olens) It is about an inch in length, of a black colour, and it3 eggs are larger than those of any other British insect. It may often be seen crossing garden walks ; and when approached or otherwise threatened, it immediately assumes a most ferocious aspect and attitude, elevating its head and opening wide its formidable jaws, raising and throwing back its tail after the manner of the scorpion, protruding its anal vesicles, and emitting a disagreeable odour. It is / O O carnivorous. VI. Clavicornes have the antennae terminating in a solid or perfoliated club, and include the Pill Beetles (Byrrhidce) and the Mimic Beetles (Histerida), The former are small insects, generally short, oval, and highly convex, although a few species found under the bark of trees are flattened. They most frequently occur in sand pits and on pathways, and when in danger withdraw their highly contractile legs into cavities prepared for them on the under side of the body, at the same time folding up their antennae and remaining motionless. In this condition they may readily be mistaken for oval seeds or pills, hence the common name. The Mimic Beetles (Plate VII. fig. 13) seldom exceed one-third of an inch in length, and are of very solid consistence, their elytra being so hard that the pin of the entomologist is with difficulty made to enter. They are somewhat square in form, with the upper surface highly polished, feeding chiefly on putrid substances and found in great abundance in spring on the dung of oxen and horses. Like Pill Beetles they roll themselves up on the approach of clanger and feign death with great perseverance, and to this they owe their generic name Ilister, from kistrio, a stage mimic. VII. Lamdlicornes comprise a vast assemblage of beetles, many of which, especially such as feed on flowers and living plants, are remarkable alike for beauty of form and splendour of colour. They are distinguished_ by the form of their antenme, which always terminate in a club composed of several leaf-like joints, disposed like the spokes of a fan, the leaves of a book, or the teeth of a comb, or in a series of funnels placed above and within each other. The males often differ from the females in having horn-like projections on the head and thorax, and in the greater size of their mandibles. They are all winged insects, although somewhat dull and heavy in their flight ; and alike in the larval and perfect states they are herbivorous, feeding either on living vegetation and flowers or on putrescent plants and excrementitious substances. The following species may be regarded as illustrative of the most important subdivisons of the Lamellicorn Beetles : Stag Beetles (Lucanidai) (Plate VIII. fig. 14), with the club of the antennae com posed of leaflets disposed perpendicularly to its axis like the teeth of a comb, owe their most striking feature to the immense development of the mandibles in the males, the purpose served by these formidable looking organs being by no means fully understood. The males appear to be more numerous than the females, and fierce contests take place among the former for possession of the latter. The Stag Beetle (Lucanus cerviis), of a uniform brown colour, measures 2 inches in length including the mandibles, and is the largest of British beetles. It inhabits woods, passing its immature stages in the interior of the oak and beech, and may be seen flying in the evening in search of the female. It has a patch of golden-coloured hair towards the base of the foreleg with which it cleans its antennae after these have been in contact with any sticky substance. After coupling and depositing their eggs both sexes soon die. The Dor Beetle (Geotrupes stercorarius) is the type of a large tribe of dung-eating beetles (Plate VII. figs. 21, 25, 26). It is a black insect, with brilliant metallic blue or purple reflections on the under side, and well known as " wheeling its drowsy flight " during fine evenings. This it does in search of a patch of cow-dung, through which it makes its way until reaching the ground, where it bores a perpendicular tunnel about 8 inches deep, and as wide as a man s finger ; then ascending to the surface it conveys a quantity of dung to the bottom, and on this it proceeds to deposit an egg ; another layer of the same material and another egg follow until the entire shaft is filled. The larvae on leaving the egg thus find themselves surrounded with their appropriate food. The Sacred Beetle of Egypt, Ateuchus sacer (Plate VII. fig. 29), somewhat resembles the Dor in form and habits. After depositing her egg on a piece of dung the female rolls the mass about in the sun shine with her forelegs until it forms a rounded ball. The process of hatching is thus accelerated, and a thin hardened crust is formed around the softer material inclosing the egg. A hole is then dug in the earth by means of its powerful forelegs, into which the ball is rolled and then covered over with earth, where it remains until fully developed. Those beetles show great perseverance in conveying the egg-laden pellets to their destination, fre quently carrying them over rough ground on the broad flat surface of their heads, and seeking, when unable singly to complete the work, the assistance of their fellows. Two species of Sacred Beetles were worshipped by the ancient Egyptians, who regarded them as emblems of fertility, and as representing the resurrection of the soul, owing to their sudden appearance in great numbers on the banks of the Nile after the annual subsidence of that river. They form a conspicuous feature in the hieroglyphics of that nation, and are found sculptured on their monuments, sometimes of gigantic size. They were also formed into separate figures, as seals and amulets, made of gold and other precious materials, and hung around the necks of the living, or buried along with their mummies. The insect itself is sometimes found in their coffins. The male Hercules Beetle (Scarabceus hercules) of Guiana has the head pro duced into an enormous horn, bent downwards at the ex tremity, and clothed on the under surface with a reddish brown pile, and measures 6 inches in length. The Cock

chafers, Melolontkidce (Plate VII. fig. 2S), have a short