Homes Without Hands: Being a Description of the Habitations of Animals, Classed According to Their Principle of Construction - Page 115

When viewed from the outside it would hardly be recognized for the habitation of an insect, for it looks like a large lump of hardened clay, about as large as an ordinary French roll, and not very unlike it in shape. On a closer inspection, a number of little holes may be seen, and these apertures afford an unfailing indication as to the real nature of the clay lump. Fig. 2 represents the external appearance of one of these cells.

Supposing that a queen Termite cell be cut vertically, so that the knife passes through either of the little round holes, it will present an appearance which is shown at Fig. 1. The large hollow of the cell is nearly filled by the body of the female, whose head and thorax are seen in the cavity. On either side is a section of the little holes, which are shown to be cylindrical passages communicating with the interior of the cell. The worker Termites, being very small, can traverse these passages with perfect ease, while the enormous body of the female is utterly unable to pass.

Termite Cell.

Through these passages the workers are continually passing, some entering with empty jaws, and others emerging, each holding between its mandibles an egg, which it is conveying to the nurseries. So rapidly are the eggs laid, that the workers are fully employed in carrying them out and placing them under the charge of the nurses.

The contrast in size between the workers and the queen can easily be seen by reference to the illustration. At Fig. 5 is shown the queen, and in the right hand of Fig. 1 is seen one of the workers passing through the tunnel. None but the workers can pass through so small an aperture, for the fighters or soldiers are of very much greater size than the workers, as may be seen at Fig. 4.

The queen, however, is necessarily very much reduced in size, as, if she had been drawn of her full dimensions, she would have occupied the whole length of the drawing. Before she is immured in the royal cell she is by no means a large insect, the abdomen being in ordinary proportion to the thorax and head; but when she has been fairly installed in her office her abdomen begins to enlarge, until it becomes so enormous that she is totally unable to move, and therefore her enforced prison is so far from being a hardship that it is a necessary protection for her huge and soft body, which is several hundred times larger than that of her mate. Large indeed she must be, as she is calculated to produce, on the average, rather more than thirty million eggs.

Figs. 3, 3 show the appearance of the royal cell when split open longitudinally, the recess which contains the queen being seen nearly in the centre. All the drawings were taken from specimens in the British Museum, and in the cell which is here figured the outline of the queen is quite perceptible, having been impressed on the interior of the cell. The mode by which it is enlarged is also shown, a farther enlargement having been begun, but cut short by the demolition of the nest. The cells vary very much in size, probably in accordance with the dimensions of the inclosed queen. I have seen them as large as cocoa-nuts, and of an extraordinary weight, the greater portion of the mass being solid clay.

THE following illustration represents a most singular structure, which is in the collection of the British Museum, and may be seen in the nest-room.

It is hardly possible to imagine any object which less resembles an insect's nest. It might very well be taken for a sponge, did sponges grow in the forests of Cayenne. It much resembles a fungus, and might be mistaken for an overgrown and partially decayed puff-ball. If inspected closely it seems to be made of the same fungus that furnishes the German tinder, and is indeed, like that substance, very useful as a means of stopping the flow of blood.

The real material, however, of which the nest is made is formed of the short cottony fibres which fill the seed-pods of the cotton-tree (Bombax ceiba). The fibre is so short that it is incapable of being woven into fabrics, though it might possibly be made useful in the manufacture of paper, its texture being peculiarly soft and silky. The only uses to which it is at present applied are stuffing mattresses and pillows, and packing delicate goods, and heading the tiny poisoned arrows which are projected through the blow-gun of the native.

Fungus Ant.

These ants, however, find the fibre useful for their work, and contrive to weave it so dexterously that the individuality of the fibres is lost, and they are all made into a compact and uniform mass. The size of the nests varies, but is sometimes very considerable, a full-sized nest being often as large as a man's head.

The ant itself is rather a curious little creature, dark in color, covered with many angular protuberances, and being remarkable for a couple of long, sharp spines that project from the thorax, one on either side. Its scientific names, Polyrachis bispinosa, are given in consequence of these projections, the first name being composed of two Greek words signifying many-peaked, and the second being formed from two Latin words signifying two-spined.

THERE are many insects whose habitations are peculiarly annoying to mankind, and yet are extremely interesting to those who take an interest in the workings of instinct. Chief among these insects is the well-known CLOTHES MOTH. There are several allied species which popularly go by this name, but the most plentiful is that which bears the scientific title of Tinea vestianella. These destructive little creatures are proverbially injurious to clothes, especially if the garments be made of wool or furs, vegetable fabrics being not to their taste. Some species affect dried insects, and are, in consequence, extremely baleful to the entomologist; while their ravages on furs and feathers, and even on leather itself, render them the dread of those who, like myself, possess collections of natural history or ethnology.

In their winged state the moths themselves do no direct harm; but their young are doubly mischievous, firstly, because they devour the fabrics in which they live, and secondly, because they cut up the cloth, fur, or feathers in order to obtain material for their home. Possibly for the sake of concealment as well as protection, the larva instinctively forms a habitation which entirely covers its white body, and which is almost imperceptible to the eye, because it is formed of the same material as the fabric on which it lies.

The habitation is tubular in form, though not exactly cylindrical, being rather larger in the middle than at the ends, and open so as to allow the extremities of the caterpillar to protrude. One object in this structure is to enable the inmate to turn in its cell, an operation which must necessarily be performed whenever the tubular home is enlarged. The process of enlargement is continually going on, and it is in consequence of this proceeding that so much material is used.

The manner in which the little creature enlarges its home is as follows:

Without quitting its tubular home, it cuts a longitudinal slit throughout half its length or so, and opens the case to the required width. It then proceeds to weave a triangular piece of webbing, with which it fills up the opened slit, and joins the edges with perfect accuracy. As one end of the case is now larger than the other, the caterpillar turns its attention to the other end, cuts it open, widens it, and fills up the gap precisely as it had done to the first part. When the soft tube is sufficiently widened, it is lengthened by the addition of rings to each extremity.

By taking advantage of this peculiar method of house-making, observant persons have forced the Clothes Moth to make their tubular homes of any color and almost of any pattern. By shifting the caterpillar from one colored cloth to another, the required tints are produced, and the pattern is gained by watching the creature at work, and transferring it at the proper season. For example, a very pretty specimen can be produced by turning out of its original home a half-grown caterpillar, and putting it on a piece of bright green cloth. After it has made its tube it can be shifted to a black cloth, and when it has cut the longitudinal slit, and has half filled it up, it can be transferred to a piece of scarlet cloth, so that the complementary colors of green and scarlet are brought into juxtaposition, and “thrown out” by the contrast with the black.

The caterpillar is not very particular as to the kind of material which it employs and on which it feeds. Mr. Rennie makes the following observations on one of these creatures, whose proceedings he had watched. “The caterpillar first took up its abode in a specimen of the ghost moth (Hepialus humuli), where, finding few suitable materials for building, it had recourse to the cork of the drawer, with the chips of which it made a structure almost as warm as it would have done from wool. Whether it took offense at our disturbing it one day, or whether it did not find sufficient food in the body of the ghost moth, we know not; but it left its cork house, and traveling about eighteen inches, selected the ‘old lady’ moth (Mormo maura), one of the largest insects in the drawer, and built a new apartment, composed partly of cork as before, and partly of bits clipped out of the moth’s wings.

“We have seen these caterpillars form their habitations of every sort of insect, from a butterfly to a beetle, and the soft, feathery wings of moths answer their purpose very well; but when they fall in with such hard materials as the musk beetle, or the large scolopendra of the West Indies, they find some difficulty in the building.

“When the structure is finished, the insect deems itself secure to feed on the materials of the cloth, or other animal matter within its reach, provided it is dry, and free from fat or grease, which Réaumur found it would not touch. For building, it always selects the straightest and loosest pieces of wool; but for food it prefers the shortest and most compact; and to procure these, it eats into the body of the stuff, rejecting the pile or nap, which it necessarily cuts across at the origin and permits to fall, leaving it threadbare, as if it had been much worn.”

From the account which has just been given, it is evident that the caterpillar must be able to turn completely round in its case, and in order to enable it to perform this evolution, the tube is much wider in the middle than at the ends.

The instinct of the parent moth enables it to discover with astonishing certainty any substance which may afford food to its future young. Stuffed birds suffer terribly from the moth, because the arsenical soap with which the skins are preserved does not extend its poisonous influence to the feathers. I have known whole cases of birds to be destroyed by the moth, all the feathers being eaten, and nothing left but the bare skins.

Even the most deadly poison, corrosive sublimate, is not effectual, unless it settles on every feather. There is now before me a stuffed golden-eye duck, preserved by myself, the close plumage of which has partially thrown off the poisoned solution, and has consequently admitted the moth in small patches of feathers, especially about the neck. There is also in my collection a Kaffir shield, made of an ox-hide, which has been washed with the solution, and is almost entirely secure from the depredations of the moth. Yet there are one or two spots where a thong has protected the hair, and in those very spots the pertinacious moths have laid their eggs, and, in one or two instances, the caterpillars have succeeded in attaining their perfect state.

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