The majority of these animals are natives of tropical countries, though two species are indigenous to Europe; one of which, thought to have been imported, is come so near to us as Bourdeaux. Their society consists of five different descriptions of individuals: workers or larvae, nymphs or pupae, neuters or soldiers males, and females.

1. The workers or larvae, answering to the hymenopterous neuters, are the most numerous, and, at the same time, most active part of the community; upon whom devolves the office of erecting and repairing the buildings, collecting provision, attending upon the female, conveying the eggs, when laid, to the nurseries, and feeding the young larvae till they are old enough to take care of themselves. They are distinguished from the soldiers by their diminutive size, by their round heads, and shorter mandibles.

2. The nymphs, or pupae, differ in nothing from the larvae, and probably are equally active, except that they have rudiments of wings, or rather wings folded up in cases.

3. The neuters are much less numerous than the workers, bearing the proportion of one to one hundred, and exceeding them greatly in bulk. They are also distinguishable by their long and large heads, armed with very long tubulate mandibles. Their office is that of sentinels; and when the nest is attacked, to them is committed the task of defending it. These neuters seem to be a kind of abortive females, and there is nothing analogous to them in any other department of entomology.

4 and 5. Males and females, or the insects arrived at a state of perfection, and capable of continuing the species. There is only one of each in every separate society ; they are exempted from all participation in the labours and employments occupying the rest of the community, that they may be wholly devoted to the furnishing of a constant accession to the population of the colony. Though at their first disclosure from the pupae they have four wings, like the female ants, they soon cast them; but they may then be distinguished from the blind larvae, pupae, and neuters, by their large and prominent eyes.

The different species of Termites, which are numerous, build nests of very various forms. Some construct upon the ground a cylindrical turret of clay, about three-quarters of a yard high, surrounded by a projecting conical roof, so as in shape considerably to resemble a mushroom, and composed interiorly of innumerable cells, of various figures and dimensions. Others prefer a more elevated site, and build their nests, which are of different sizes, from that of a hat to that of a sugar-cask, and composed, of pieces of wood glued together, amongst the branches of trees, often seventy or eighty feet high. But by far the most curious habitations, are those formed by the Termes bellicosus, a species very common in Guinea, and other parts of the coasts of Africa, of whose proceedings we have a very particular and interesting account in the 71st volume of (he Philosophical Transactions.

These nests are formed entirely of clay, and are generally twelve feet high, and broad in proportion; so that when a cluster of them, as is often the case in South America, are placed together, they may be taken for an Indian village, and are in fact sometimes larger than the huts which the natives inhabit. The first process in the erection of these singular structures, is the elevation of two or three turrets of clay, about a foot high, and in shape like a sugar-loaf. These, which seem to be the scaffolds of the future building, rapidly increase in number and height, until at length being widened at the base, joined at the top into one dome, and consolidated all around into a thick wall of clay, they form a building of the size above-mentioned, and of the shape of a haycock, which, when clothed, as it generally soon becomes, with a coating of grass, it at a distance very much resembles. When the building has assumed this its final form, the inner turrets, all but the tops, which project like pinnacles from different parts of it, are removed, and the clay employed over again in other services. It is the lower part alone of the building that is occupied by the inhabitants; the upper portion, or dome, which is very strong and solid, is left empty, serving principally as a defence from the vicissitudes of the weather and the attacks of natural or accidental enemies, and to keep up in the lower part a genial warmth and moisture, necessary to the hatching of the eggs and cherishing of the young ones. The inhabited portion is occupied by the royal chamber, or habitation of the king and queen; the nurseries for the young; the storehouses for food; and innumerable galleries, passages, and empty-rooms, arranged according to the following plan: In the centre of the building, just under the apex, and nearly on a level with the surface of the ground, is placed the royal chamber, an arched vault of a semi-oval shape, or not unlike a long oven; at first not above an inch long, but enlarged, as the queen increases in bulk, to the length of eight inches or more. In this apartment the king and queen constantly reside, and, from the smallness of the entrances, which are barely large enough to admit their more diminutive subjects, can never possibly come out; thus, like many human potentates, purchasing their sovereignty at the dear rate of the sacrifice of liberty. Immediately adjoining the royal chamber, and surrounding it on all sides to the extent of a foot or more, are placed the royal apartments, an inextricable labyrinth of innumerable arched rooms, of different shapes and sizes, either opening into each other, or communicating by common passages, and intended for the accommodation of the soldiers and attendants, of whom many thousands are always in waiting on their royal master and mistress.

Next to the royal apartments come the nurseries and the magazines. The former are invariably occupied by the eggs and young ones, and, in the infant state of the nest, are placed close to the royal chamber; but when the queen's augmented size requires a larger apartment, as well as additional rooms for the increased number of attendants wanted to remove her eggs, the small nurseries are taken to pieces, rebuilt at a greater distance, a size larger, and their number increased at the same time. In substance they differ from all the other apartments, being formed of particles of wood, apparently joined together with gums. A collection of these compact, irregular, and small wooden chambers, not one of which is half an inch in width, is inclosed in a common chamber of clay, sometimes as big as a child's head. Intermixed with the nurseries, lie the magazines, which are chambers of clay, always well stored with provisions, consisting of particles of wood, gums, and the inspissated juices of plants.