CHAPTER V.
TERMITES.
The habits of the Termites, or so-called White Ants, have not been so closely studied as they deserve. Our chief knowledge concerning them is derived from the observations of Jobson, in his 'History of Gambia;' Bastian, in 'The Nations of Eastern Asia;' Forsteal, Lespès, König, Sparman, Hugen, Quatrefages, Fritz Müller, and most of all, Smeathman, in 'Philosophical Transactions,' vol. lxxi. In Africa these insects raise their hills to a height of between ten and twenty feet, and construct them of earth, stones, pieces of wood, &c., glued together by a sticky saliva. The hills are in the form of a cone, and so strong that it is said the buffaloes are in the habit of using them as watch-towers on which to post sentries, and that they will even support the weight of an elephant. The growth of these gigantic mounds is gradual, increasing with the increase of the population. From the mound in all directions there radiate subterranean tunnels, which may be as much as a foot in width, and which serve as roadways. Besides these tunnels there are a number of other subterranean tubes, which serve the purpose of drainage to carry off the floods of water to which the nest is exposed during tropical showers. Büchner calculates that a pyramid built by man on a scale proportional to his size would only equal one of these nests if it attained to the height of 3,000 feet. The following is this author's description of the internal structure:—
These internal arrangements are so various and so complicated that pages of description might be written thereupon. There are myriads of rooms, cells, nurseries, provision chambers, guard-rooms, passages, corridors, vaults, bridges, subterranean streets and canals, tunnels, arched ways, steps, smooth inclines, domes, &c., &c., all arranged on a definite, coherent, and well-considered plan. In the middle of the building, sheltered as far as possible from outside dangers, lies the stately royal dwelling, resembling an arched oven, in which the royal pair reside, or rather are imprisoned; for the entrances and outlets are so small, that although the workers on service can pass easily in and out, the queen cannot; for during the egg-laying her body swells out to an enormous size, two or three thousand times the size and weight of an ordinary worker. The queen, therefore, never leaves her dwelling, and dies therein. Round the palace, which is at first small, but is later enlarged in proportion as the queen increases in size until it is at least a yard long and half a yard high, lie the nurseries, or cells for the eggs and larvæ; next these the servants' rooms, or cells for the workers which wait on the queen; then special chambers for the soldiers on guard, and, between these, numerous store-rooms, filled with gums, resins, dried plant-juices, meal, seeds, fruits, worked-up wood, &c. According to Bettziech-Beta, there is always in the midst of the nest a large common room, which is used either for popular assemblies or as the meeting and starting point of the countless passages and chambers of the nest. Others are of the opinion that this space serves for purposes of ventilation.
Above and below the royal cell are the rooms of the workers and soldiers which are specially charged with the care and defence of the royal pair. They communicate with each other, as well as with the nursery-cells and store-rooms, by means of galleries and passages which, as already said, open into the common room in the middle under the dome. This room is surrounded by high, boldly projected arched ways, which lose themselves further out in the walls of the countless rooms and galleries. Many roofs outside and in protect this room and the surrounding chambers from rain, which, as already said, is drained away by countless subterranean canals, made of clay and of a diameter of ten or twelve centimetres. There are also, under the layer of clay covering the whole building, broad spirally winding passages running from below to the highest points, which communicate with the passages of the interior, and apparently, as they mainly consist of smooth inclines, serve for carrying provisions to the higher parts of the nest.[71]
The termites, like many species of true ants, are divided into two distinct castes, the workers and the soldiers. If a breach is made in the walls of the dome the soldiers rush out to meet the enemy, and fight desperately with any enemy that they may find. Here, again, I cannot do better than quote Büchner's epitome of facts:—
If the assailant withdraws beyond their reach and inflicts no further injury, they retire within their dwelling in the course of half an hour, as though they had come to the conclusion that the enemy who had done the mischief had fled. Scarcely have the soldiers disappeared when crowds of workers appear in the breach, each with a quantity of ready-made mortar in its mouth. As soon as they arrive they stick this mortar round the open place, and direct the whole operation with such swiftness and facility that in spite of their great number they never hinder each other, nor are obliged to stop. During this spectacle of apparent restlessness and confusion the observer is agreeably surprised to see arising a regular wall, filling up the gap. During the time that the workers are thus busied the soldiers remain within the nest, with the exception of a few, which walk about apparently idly, never touching the mortar, among the hundreds and thousands of workers. Nevertheless one of them stands on guard close to the wall which is being built. It turns gently each way in turn, lifting its head at intervals of one or two minutes to strike the building with its heavy mandibles, making the before-mentioned crackling noise. This signal is immediately answered by a loud rustling from the interior of the nest and from all the subterranean passages and holes. There is no doubt that this noise arises from the workers, for as often as the sign is given they work with increased energy and speed. A renewal of the attack instantaneously changes the scene. 'At the first stroke,' says Smeathman, 'the workers run into the many tunnels and passages which run through the building, and this happens so quickly that they seem regularly to vanish. In a few seconds they are all gone, and in their stead appear the soldiers once more, as numerous and as pugnacious as before. If they find no enemy, they turn back slowly into the interior of the hill, and immediately the mortar-laden workers again appear, and among them a few soldiers, which behave just as on the first occasion. So one can have the pleasure of seeing them work and fight in turn, as often as one chooses; and it will be found each time that one set never fight, and the other never work, however great the need may be.'[72]
Similar facts have been observed by Fritz Müller of the South American species.
The Termites, being like the Ecitons blind, like them make all their expeditions under the protection of covered ways. These are underground tunnels in all cases where circumstances permit, but on arriving at a rock or other impenetrable obstruction, they build a tubular passage upon the surface. According to Büchner,—