Читать книгу Animals of no Importance - Douglas Dewar - Страница 7

The hot weather is upon us. The time is at hand when the dweller in the plains will become a daily prisoner in his bungalow. The season approaches when men will cry aloud for the mild sunshine of the hills or the cold mists of England. Not least among these complainers will be the naturalist, whom the hot weather debars to a great extent from his favourite pursuit. Right earnestly will he long for the time when he will be able once again to study Nature in comfort. But why cry out for the unattainable? Rather let us make the best of what we have. Even within the narrow confines of the darkened bungalow Nature may be studied. For I am not the only occupier of my home. I am but one among many. Living behind pictures during the day are two nimble lizards, which come out at eventide and rove up and down the walls in search of prey. One lizard has lost his tail, having probably left it in the hands of a would-be captor. It is, however, not a very serious loss, as it can be replaced. The new tail is just beginning to show. The absence of his tail does not appear to impede him, for he stalks his prey with incomparable craft and agility; darting now here, now there, and never failing to secure the hapless insect. There would seem to be a kind of etiquette in lizard society, for never do both my lizards hunt together. No sooner is the lamp lit and hung upon the wall than one appears, but one only. The energies of one lizard more than suffice for the scouring of the lit-up hunting ground, so one stands down, while the other ruthlessly devours hundreds of unfortunate insects. But we cannot afford to sympathise with the insects, for each one killed means one tormentor the less. Cold, timid, little reptile, what a debt of gratitude we Anglo-Indians owe you! But for your efforts who can tell what our torments would be?

There are in my bungalow other beasts of prey, fierce and more voracious than any of the denizens of the jungle. One of these lives on the under side of a wicker table. There the spider spins her web. No one can have failed to notice the large abdomen of the spider: this contains the “silk” glands which open on the “spinnerets” situated at the posterior end of the animal. These glands secrete a sticky fluid, which assumes a thread-like shape as it passes through the ducts. Exposure to the atmosphere instantly converts this viscid fluid into a silk-like thread, so that the spider seems to really “spin” her web.

Having selected a suitable site for her snare, the spider secretes a short thread and fastens the free end to what will be the upper limit of the web. She then allows herself to drop, secreting a silken thread as she goes, until she reaches what will be the lower boundary of her net. Here she fixes the other end of the strand. Thus the foundation of her web is laid. The industrious creature allows herself no rest until she has completed her snare, secreting strand upon strand, and interweaving them most skilfully. She has now laid a perfect trap for the unwary fly. A spider’s web is made up of two kinds of threads; a few thicker ones, which form the highways for the spider, and a great number of very fine strands which act as the snare. Having completed operations the spider retires to a dark corner and awaits events. If fortune favours her it will not be long before a fly or other insect finds his way into the “parlour.” The amount of violence with which the web is shaken by the struggles of the victim at once informs the spider whether it is a large creature, such as a wasp, or a small one, such as a fly. Her mode of procedure varies accordingly. If a fly be caught the spider pounces down upon it with lightning rapidity, grasps it with her two front legs, and, holding on to the web by means of her two middle pairs, uses the hindermost pair, and the spinnerets to wind a net of silk round her victim. If she be not hungry she leaves her captive thus bound, figuratively speaking, hand and foot, until she needs a meal. If she be hungry she at once paralyses her prey with the poison she secretes, and then proceeds to suck out its life-blood. When she has absorbed all the nutrient matter she casts away the dry husk.

If, however, her victim be a wasp the spider approaches it very warily, taking great care to avoid the sting. She commences operations with the head, winding it round and round with silk, and then works backwards. It not infrequently happens that the wasp is too much for the spider, and bids fair to wreck her net in the violence of its struggles; the clever spider then, on the principle of “discretion is the better part of valour,” cuts the web all round the dangerous prisoner, which is thus allowed to drop away.

Each day I feed my spider. A black ant is daily sacrificed to her. Sometimes for an ant I substitute a little ball of paper. As soon as it touches the net the spider pounces down upon it only to find herself the victim of a trick which she seems to resent, for she retreats in disgust, returning later to cut away the useless encumbrance.

It was stated above that the spider is cruel and voracious. But she is worse than this—she is a cannibal. I look forward to the time of her courtship, when the male, who is smaller than the female, will timidly approach and dance before her in hopes of winning her approval. If he fails to please she will dash at him, and he will run for his life, for if she catch him she will devour him without compunction. I regret to have to relate that it often happens that even after the lady spider has accepted one of her suitors as her spouse she kills and eats him. Such are the dire tragedies that frequently occur in the seemingly peaceful bungalow!

The cricket is another of my unbidden guests. He is a cousin of the grasshoppers, and, like his relatives, a marvellous jumper, hence it is not easy to capture him; you think you have him in a corner, when, like De Wet, he escapes you. The cricket is not a favourite of mine, for his continued shrill stridulation is to me a most unpleasant sound. The males only do the chirruping; it is their love song. Bates, writing of the European field cricket, states: “The male has been observed to place himself in the evening at the entrance of his burrow, and stridulate until a female approaches, when the louder notes are succeeded by a more subdued tone, whilst the successful musician caresses with his antennas the mate he has won.” Although the chief object of stridulation is to attract the female, it is not the only one. White in his Natural History of Selborne declares that the house cricket, when surprised at night, uses its voice to warn its fellows. Dr. Scudder was able to excite a cricket to answer him by rubbing a file with a quill.

When a cricket is “calling” his legs never move, his wings, however, vibrate in a horizontal plane. So fast is the motion—24,000 vibrations a second—that the eye can scarcely follow it. If the wing-cover of a cricket be examined under the microscope there will be seen projecting from the under surface a ridge divided up into some 230 teeth. This toothed-ridge is rapidly scraped across a smooth hard projection on the lower wing, and thus the irritating sound of the cricket produced.

Most naturalists will admit that, with the exception of man, the polymorphic insects—ants, termites, bees, and wasps—are the most wonderful animals in creation. Of these four families no fewer than three are represented in the fauna of almost every bungalow. These creatures, long before man came into existence, discovered two great economic truths, that the advantages of the division of labour are great, and that in combination there is strength.

A colony of black ants will probably consist of over twenty thousand individuals. These are divided into three castes or classes—winged males, females which are winged in earlier life, and wingless sterile females or workers. The two first classes are rarely seen, for the males are allowed to die after they have performed their function, and the females stay always under-ground in the nest and lay eggs. The ants which one observes wandering about the bungalow belong to the neuter class. They do all the work. They search for food and feed the females, they look after the eggs and pupae, defend the nest, and keep it in order. Many species of ants make slaves and domesticate other insects. Lubbock has counted no fewer than five hundred and eighty-four species of crustaceans and insects which have been thus domesticated by ants. From some of these the ants extract a juice just as men obtain milk from cows. The intelligence of ants has been vastly exaggerated. Thus Huber thought that ants had a regular language. This and other assertions regarding these wonderful little creatures have been proved to be contrary to fact. There is now a tendency to go to the opposite extreme, and deny to ants powers which they really possess. Thus, because some observers saw ants carrying in their mouths what they took to be food-grains, but which were in reality the cocoons or pupae cases containing the young, it has been asserted that no ants store up grain.

My own experience, however, enables me to vouch for the grain carrying habits of the black ant so common in the bungalow.

In one of the ante-rooms a considerable quantity of barley was one day upset on to the ground. By the next morning nearly all this grain had been removed by the black ants. These industrious little creatures had piled it up in the next room; they had in one night removed sufficient barley to make a heap nearly four inches high.

For their size ants are endowed with remarkable strength. An ant will carry off, apparently without the least exertion, a grain of corn or other load three times its own weight.

The wasp cannot be called a general favourite, for most people only know it by its sting. The sting, however, is really an instrument for depositing eggs, and is only incidentally turned into a weapon of offence or defence. A wasp will never sting unless frightened. The queen wasp is the finest specimen of feminine industry and maternal devotion found in the animal world. At the beginning of the hot weather the royal lady awakes from her torpor and founds a new colony. “I want you,” writes Grant Allen, “to understand the magnitude of the task this female Columbus sets herself—Columbus, Cornelia, and Cæsar in one—the task not only of building a Carthage, but also of peopling it. She has no hands to speak of, but her mouth, which acts at once as mouth, and hands, and tools, and factory, stands her in good stead in her carpentering and masoning.” Her nest is a veritable work of art. It is composed of a vast number of rooms, in each of which she lays an egg. When these hatch she carefully feeds and tends the larvæ, the while laying more eggs and extending the nest. The first perfect wasps to emerge are the workers; they then relieve the over-worked queen of all duties except that of laying eggs. Of these a queen wasp will produce five or six thousand.

Disliked even more than the wasp is the white ant, which, by the way, is not an ant at all, belonging as it does to quite a different order of insects. Our dislike of white ants, or Termites as they are more properly called, is certainly well-founded, for in the bungalow they are an unmitigated nuisance. Out of doors, however, they perform a most useful function. They are for countries with hot dry climates what the earthworms are for damp temperate regions, nature’s ploughmen.

As every Anglo-Indian knows, these “worst abused of all living vermin” feed upon dried wood.

But the succulent body of the white ant is a morsel to the taste of every bird, and as the body of the termite is so conspicuous it has to approach under cover all objects not actually on the ground. The white ant, therefore, builds a tunnel as it progresses. These trenching tunnels frequently appear on the bungalow walls, and marvellously quickly do they grow. The termites work from the inside, and at the incomplete end of the passage they may be seen in numbers adding fresh pieces of mould. The earth for these tunnels is usually brought up from under-ground; thus much of the deeper soil is carried to the surface.

With the first advent of the rains we are invaded by a new form of the white ant—the winged form. They come in thousands, they are the young males and females ready to assume sexual relations, and to become the kings and queens. The swarming of the white ant constitutes a veritable harvest for spiders, lizards, bats, toads, &c., and glad are we that these winged forms have so many enemies that prey upon them, for although the males and females themselves do not attack wood, each female is able to produce in her time not far short of a million eggs, most of which will develop into the wood-infesting forms.

Want of space prevents me from even enumerating the other inmates of the bungalow, the mice, rats, toads, flies, moths, fish-insects, ticks, mosquitoes, and other parasites. These creatures are all around us, each living its own little life, each fulfilling its purpose in the plan of the universe. There is, indeed, a considerable bungalow fauna, each member of which forms a study in itself, a study which any man, be he scientist or no, may take up, and even if rewarded by no great discovery, he will not look upon his labour as lost, for he will at least have passed profitably and with pleasure what would otherwise have proved many weary hours of imprisonment in the bungalow.