APPENDIX. ON THE INSTINCTS OF SOCIAL INSECTS. A GENERAL account has been elsewhere given (ANIM. PHYSIOL., Chap. XIV.) of the habits and instincts of the Hive Bee; and a similar sketch will be here given of the History of the Termites or White Ants, and of that of the Common Ants. The Termites, or White Ants, belong to the Order Neuroptera (§ 675); and are the only true social insects contained in that group. Next to the Locusts, they may be reckoned the most destructive Insects known to Man; since not only articles of food, but clothing, fences, trees, and even houses, fall before their devouring jaws. As they are confined, with scarcely any exception, to tropical climates, we are only acquainted with their ravages by the reports of travellers who have visited those regions; but these reports are such, as we may fully trust to.The Termites live in immense communities, consisting of kings and queens, soldiers and labourers. The kings and queens are perfect insects, male and female; and their office is solely to increase their kind. The soldiers appear to be the pupa, stopped in their development, so as never to possess wings or to acquire the reproductive organs; it is their office to attack every object or living thing, that in any way injures or endangers the safety of the nest; and this duty they perform with the most reckless bravery, the labourers retiring within the nest during the time of danger. The labourers are probably to be regarded as the larva, alike checked in their development; their offices are manifold,their duty being to take the eggs from the queen as fast as she lays them, to convey them to the nurseries and to tend them until hatched, and to feed the young, store provisions, build the nest, repair damages, and perform every kind of labour requisite for the good of the community, The nests of the Termites are so numerous all over the island of Bananas and the adjacent Continent of Africa, that it is scarcely 568 INSTINCTS OF TERMITES, OR WHITE ANTS. possible to stand upon any open place, such as a rice-plantation or other clear spot, where one or more of these buildings is not to be seen within fifty paces. In some parts near Senegal, as mentioned by Adanson, their number, magnitude, and closeness of situation, make them appear like the villages of the natives. These buildings are usually termed "hills" from their outward appearance, which is that of little hills, generally pretty much in the form of sugar-loaves, and about ten or twelve feet in height. These hills continue quite bare until they are six or eight feet high; but in time become, like the rest of the earth, almost covered with grass and other plants; and in the dry season, when the herbage is burnt up by the rays of the sun, they somewhat resemble very large hay-cocks. The exterior of the building consists of one large shell or domed wall; which is large and NESTS OF TERMITES The large nests, of which one is cut open vertically to show the interior, are those of the Termes bellicosus. The small nest (a) in the tree, is that of the Termes arborum; and at b is seen the arched gallery, by which it communicates with the ground. strong enough to shelter the interior from the weather, and to protect the inhabitants from the attacks of most of their enemies. It also serves to collect and preserve a regular degree of genial warmth and moisture; which seems very necessary for hatching the eggs and cherishing the young ones. The interior is divided, with great regularity and contrivance, into a great number of INSTINCTS OF TERMITES, OR WHITE ANTS. 569 apartments; some of which are intended for the residence of the kings and queens, and for the rearing of their numerous progeny; whilst others serve as magazines, and are always found well filled with stores and provisions. These hills make their first appearance above ground, by a little turret or two, in the shape of sugar-loaves; which only rise to the height of a foot, or a little more. Soon afterwards, at some little distance, while the former are increasing in height and size, the Termites raise others; and so go on increasing the number, and widening them at the base, till their works below are covered with these turrets, which they always raise the highest and largest in the middle; they then, by filling-up the intervals between each turret, collect them, as it were, into one dome. They are not very curious or exact about these turrets, except in making them very solid and strong; and when, by the junction of them, the dome is completed (for which purpose the turrets answer as scaffolds), they take away the middle ones entirely, except the tops, which, joined together, form the crown of the cupola; and they apply the clay to the building of the works within, or to the erection of fresh turrets for the purpose of raising the hillock still higher. The royal chamber, so called on account of its being adapted for, and occupied by, the king and queen, is situated near the centre of the hillock. It resembles the shape of an egg cut in half lengthways, and is at first not above an inch in length; it is afterwards increased, however, to six or eight inches, or even more, in proportion to the size of the queen (§ 675). The floor and roof of this chamber are very solid, and are composed of hardened clay. Its walls are pierced by several entrances, which will admit the soldiers and labourers, but which are not large enough to allow the king and queen (who is, at full size, a thousand times the weight of a king) to pass out. It is surrounded on all sides by a series of chambers, which may be called the royal apartments, and which are occupied by the soldiers and labourers that guard the pair, on whose safety depends the happiness, and probably even the existence, of the whole community. These apartments, being connected together by openings and passages, form an intricate labyrinth, which extends a foot or more in diameter from the royal chamber on every side; and they are surrounded by the magazines and nurseries. The former are chambers of clay; and are always well filled with a kind of provisions, which appear to consist of the gums or other thick juices of plants. The nurseries, which are so called because they 570 INSTINCTS OF TERMITES, OR WHITE ANTS. always are found to contain eggs and young ones, are entirely composed of wooden materials, seemingly joined together with gums. These are placed as near as possible to the royal apartments. When the nest is in the infant state, they are close to the royal chamber; but as, in process of time, the queen enlarges, it becomes necessary to enlarge this chamber for her accommodation; and as she then lays a greater number of eggs, and requires a greater number of attendants, so is it necessary to enlarge and increase the number of the adjacent apartments; for which purpose, the small nurseries that were at first built are taken to pieces, and are rebuilt a little farther off. The nurseries are inclosed in chambers of clay, like those which contain the provisions, but much larger. In the early state of the nest they are not larger than a hazel-nut; but in old hills, they are often as large as the head of a child a year old. Under the dome is a large open space, which is surrounded by three or four large arches of a somewhat gothic form; this space may perhaps be intended to equalise the temperature of the chambers below, by preventing either the sun or the cold air from at once affecting the latter. Beneath the lowest apartments are found a set of large passages, which communicate with all the chambers of the interior, and also with the galleries that diverge from the nest in various directions. These passages, which are thickly lined with the same kind of clay as that of which the hill is composed, ascend the inside of the shell in a spiral manner; winding round the whole building up to the top, and intersecting each other at different heights, and communicating with the various chambers by galleries branching out from them. From the bottom of these are several large galleries, which lead downwards into the ground below, sometimes to the depth of three or four feet; these are mines or quarries, whence the Termites obtain the fine gravel and clay, which they work up in their mouths to the consistence of mortar; and then use in the construction of their buildings. Other galleries extend horizontally beneath the ground, at a small depth below its surface, to a great distance. Sometimes these passages cannot be continued under ground in the required direction; and the Termites then make pipes or covered-ways along its surface, composed of the same materials with the nests. These they continue, with many windings and ramifications, for great lengths; and they construct, where it is possible, subterranean pipes running parallel with them, into which they may sink and save themselves, if their galleries above ground are |