or Bug, in zoology, a genus of insects belonging to the order of hemiptera. The rostrum is inflected. The antennae are longer than the thorax. The wings are folded together cross-wise; the upper ones are coriaceous from their base towards their middle. The back is flat; the thorax margined. The feet are formed for running.

This genus is divided into different sections, as follows: 1. Those without wings. 2. Those in which the escutcheon is extended so far as to cover the abdomen and the wings. 3. The coleopterati, whose elytra are wholly coriaceous. 4. Those whose elytra are membranaceous; these are very much depressed like a leaf. 5. In which the thorax is armed on each side with a spine. 6. Those which are of an oval form, without spines on the thorax. 7. In which the antennae become falcateous towards their point. 8. Those of an oblong form. 9. Those whose antennae are falcateous, and as long as the body. 10. Those which have their thighs armed with spines. 11. Those whose bodies are long and narrow. Linnaeus enumerates no fewer than 121 species, to which several have been added by other naturalists. A very peculiar species was discovered by Dr Sparman at the Cape, which he has named Cimex paradovus. He observed it as at noon-tide he sought for shelter among the branches of a shrub from the intolerable heat of the sun. "Tho' the air (says he) was extremely still and calm, so as hardly to have shaken an apple leaf, yet I thought I saw a little withered, pale, crumpled leaf, eaten as it were by caterpillars, fluttering from the tree. This appeared to me so very extraordinary, that I thought it worth my while suddenly to quit my verdant bower in order to contemplate it; and I could scarcely believe my eyes, when I saw a live insect, in shape and colour resembling the fragment of a withered leaf, with the edges turned up and eaten away, as it were, by caterpillars, and at the same time all over beset with prickles. Nature, by this peculiar form, has certainly extremely well defended and concealed, as it were in a mask, this insect from birds and its other diminutive foes; in all probability with a view to preserve it, and employ it for some important office in the system of her economy; a system with which we are too little acquainted, in general too little investigated, and, in every part of it, can never sufficiently admire with that respect and veneration which we owe to the great Author of nature and Ruler of the universe."

The larvae of bugs only differ from the perfect insect by the want of wings; they run over plants; grow and change to chrysalids, without appearing to undergo any material difference. They have only rudiments of wings, which the last transformation unfolds, and the insect is then perfect. In the two first stages they are unable to propagate their species. In their perfect state, the female, fecundated, lays a great number of eggs, which are often found upon plants, placed one by the side of another; many of which, viewed through a glass, present singular varieties of configuration. Some are crowned with a row of small hairs, others have a circular fillet; and most have a piece which forms a cap; this piece the larva pushes off when it forces open the egg. Released by nature from their prison, they overspread the plant on which they feed, extracting, by the help of the rostrum, the juices appropriated for their nourishment; even in this state, the larvae are not all so peaceably inclined; some are voracious in an eminent degree, and spare neither sex nor species they can conquer. In their perfect state they are mere cannibals, glutting themselves with the blood of animals; they destroy caterpillars, flies, and even the coleopterous tribe, whose hardness of elytra one would imagine was proof against CIMICIFUGA against their attacks, have fallen an easy prey to the sharp piercing nature of the rostrum of the bug, and the uncautious naturalist may experience a feeling severity of its nature. The cimex lectularius or house-bug, is particularly acceptable to the palate of spiders in general, and is even sought after by wood-bugs; which is not indeed surprising, when the general voracity of this genus is considered.

The methods of expelling house-bugs are various, as oil of turpentine, the smoke of corn-mint, of narrow-leaved wild cereals, of herb-robert, of the reddish agaric, of mustard, Guinea pepper, peats or turf, &c. (See also Bug and CIMICIFUGA).