Homes Without Hands: Being a Description of the Habitations of Animals, Classed According to Their Principle of Construction
In the British Museum there is one of these tubes, which tells a curious story, and shows that the spider which made it had chosen cultivated ground for its residence. About three inches from the mouth of the tube there is a tough, leathery flap, the object of which is not very apparent. A closer examination shows that this flap was a disused trap-door, and that the spider had lengthened its cell and made a second door at the new entrance. This fact proved that the ground had increased in thickness since the spider completed its habitation, and that the addition to the surface was very rapid, for the spider is not remarkable for longevity, and yet, in its short life, three inches of soil had covered the entrance to its silken cell. Evidently the creature had burrowed in cultivated soil, most probably in a garden, and in process of tilling the ground, a spadeful or two of earth had been thrown over the trap-door. Being thus imprisoned, the spider had no other resource but to push its way through the earth, lengthen its tube, and make another door level with the new surface.
The spider itself is an ugly creature, with rather short, but very powerful legs, and a most formidable pair of fangs. These fangs are notable for the fact that their bases are furnished with a series of sharply-pointed barbs. This peculiarity has given to the spider the generic name of Cteniza, this title being derived from a Greek word signifying a comb. The abdomen is very large, round, and firm, and from its tip projects the spinnerets, by means of which the silken tunnel is made. Altogether, it has so crustacean an aspect, that, in common with many other species, it is called by the French the Crab Spider. The length of the specimen now before me is about an inch and a quarter, exclusive of the legs.
It is nocturnal in its habits, and during the night it leaves its burrow and hunts for prey. Insects of various kinds fall victims to this spider, and at the bottom of its tunnel may be found the relics of its feast, often including the remains of tolerably large beetles. If, when it is within its home, the lid be lifted gently, the spider hastens to the entrance, hooks its hind legs to the silken lining of the lid, and the fore legs to the side of the tube, and resists with all its might. Some writers have averred that it employs the curved fangs for this purpose, and that the comb-like array of barbs is useful in giving it a stronger hold; but a very slight examination of the spider will show that such an action would be impossible, and that even if the fangs were hitched into the silk, the barbs would have no effect whatever on the firmness of the hold.
Nothing short of actual violence will induce the Trap-door Spider to vacate the premises which it so courageously defends. It will permit the earth to be excavated around its burrow, and the whole nest to be removed, without deserting its home; and in this manner specimens have been removed and placed in positions where their proceedings could be watched. Some few months ago, several examples of the Trap-door Spider and its nest were to be seen in the reptile-room of the Zoological Gardens. Boldly as the spider guards its home, and energetic as it is while engaged in defense, it is no sooner removed from the burrow than it loses all its activity, remains fixed to the spot as if stupefied, or, at the best, walks languidly about without appearing to have any definite object in view.
Trap-door Spiders inhabit many parts of the world. In the British Museum is a curious specimen of a nest, which is furnished with two doors, one at each end. The door of one end is rather loosely and irregularly made, as is, indeed, the whole end of the nest; but, at the other extremity, the door is beautifully rounded, very smooth, and fitting with astonishing neatness into the aperture. This curious specimen was discovered in Albania, and presented by W. Wilson Saunders, Esq.
The gem of the collection, however, for accuracy and finish, is one that is the work of an Australian spider, and was found at Adelaide. Only the upper part of the tube is preserved, so as to show the valve which closes it; but no one who really takes an interest in natural history can pass this nest without pausing in admiration. The workmanship is wonderful, and the hole, with its cover, looks as if it had been made in clay, by means of the potter’s wheel, so regular and true are its outlines. The hole itself is circular, but the door is semicircular, the hinge extending across the middle of the aperture.
Two points in this door are specially worthy of notice, the one being that its edge, as well as that of the aperture, is beveled off inward, so that the accurate closure of the entrance is rendered a matter of absolute certainty. The second point is, that the outer surface of the door, together with the surrounding earth, is ingeniously covered with little projections, so that when the door is closed, the line which, on smooth ground, would have marked its presence is totally hidden. The shape of the door, too, is remarkable. Toward its hinge it is comparatively thin, but upon the edge it is very thick, solid, and heavy, so that its own weight is sufficient to keep it firmly closed. The “hinge,” to which allusion has frequently been made, is not a separate piece of workmanship, but is a continuation of the silken tube which lines the tunnel. An exact imitation of its principle may be made by taking the cover of a book, and cutting it across from the inside, until all its substance except the cloth or leather is severed, and then bending the two portions back. The cloth or leather will then form a hinge precisely similar to that of the Trap-door Spider, the pasteboard taking the place of the earthen door.
CHAPTER VII.
BURROWING INSECTS.
HYMENOPTERA.
The Saüba Ant and its Habitation.—Use of the “Parasol” Leaves.—Mr. Bates’s Account of the Insect.—Enormous Extent of the Dwelling.—The Dusky Ant.—Its Strength and Perseverance.—Man and Insect contrasted.—The Brown Ant.—Form of its Habitation.—Regulation of Temperature.—Necessity of Moisture.—How the Ant constructs Ceilings.—Mining Bees.—The Andrena and its burrowing Powers.—The Eucera.—Its Habitation and curious Method of liberating the Antennæ.—The Scolia, its Burrows and its Prey.—The Indian Sphex and its Ingenuity.—The Mellinus and Oxybelus.—Curious Method of catching Prey.—The Philanthus, its Burrow, and the Food of its Young.—The Humble-Bee—its general Habits.—Locality of its Dwelling.—Development of the Young.—The Lapidary Bee, its Colors, Disposition, and Habits.—The Wasp—its Food and Habitation.—Materials and Architecture of the Nest.—Disposition, Form, and Number of the Cells.—Biography of a Queen Wasp, and History of her Nest.—Other British Wasps and their Homes.—The Monedula and its Prey.—Boldness of the Insect, and its Uses to Travelers.—The Bembex.—Its energetic Habits, its Food, and Mode of storing the Nest.
The burrowing INSECTS now come before our notice.
Of these creatures there is much store, for, indeed, the greater number of insects are wholly or partially burrowers at some period of their existence. It frequently happens that the very insects which we most admire, which are decorated with the most brilliant colors, and which soar on the most ethereal wings, have passed the greater portion of their lives as burrowers beneath the surface of the earth.
Take, for example, the well-known May-fly, or Ephemera, so called because its existence was once thought to be comprised within the limits of a single day. How delicate are its gauzy wings; how wonderful are the iridescent tints which play over their surface with a changeful radiance, like that of the opal or the pigeon’s neck; and how marvelous is the muscular power which enables the new-born being to disport itself in the air for a period which, in comparison with our own lives, is equal to at least forty years! It never seems to weary. It wavers up and down, up and down in the air, together with myriads of its companions, and for the greater portion of its terrestrial existence is an inhabitant of the air; yet its life has not altogether been spent in amusing itself, for it has passed an existence of some three years or more hidden from human gaze.
To-day it is a bright denizen of the sunbeams, exulting in its beauty, and dancing in very rapture in the air; yesterday, it was a denizen of the mud, a slimy, crawling, repulsive creature, breathing through the medium of the water, and feeding greedily upon any prey that might come within its reach. Yesterday, had it been removed from the water and laid in the sunbeams, it would have died as with poison, and in an hour would have been reduced to a dry and withered semblance of its former self; to-day, were it to be plunged beneath the waters, it would quickly perish, and be shortly eaten by its former companions. For it is fitted for a higher position and a purer atmosphere, so that the element which but a few hours ago was its very life, has now become a present death, and the food in which it so lately reveled can no longer be received into that etherealized form.
So is it with many other insects. Some of our most tender and downy-plumed moths, whose exquisitely delicate raiment is destroyed by a touch, have entered upon their winged state while in the bowels of the earth, and have made their way through the soil without losing a single feather of the myriad plumes with which their bodies and wings are covered. Flies, too, whose slender bodies and light gauzy wings always excite our wonder, that a thing so light should contend with the world, have passed the greater part of their lives in some dark hole, where the fresh air never entered, and into which the sunbeams never cast a ray.
Were this work to be arranged according to the rigid systems of zoological schoolmen, the list of burrowing insects must have been headed by the beetles; but, as the subject of the book is to describe the peculiar dwellings which are needful for the welfare of various animals, a different arrangement is necessary, so that a well-built home takes precedence over a well-developed animal. If we wish to select an order of insects which surpasses every other in the variety and excellence of their burrows, we turn at once to the Hymenoptera, a large and important group of insects, which includes the wasps, bees, ants, saw-flies, ichneumons, and one or two other families. The greater number of these insects burrow in the ground; but others are remarkable for their wonderful powers of excavating the hardest wood, and of forming therein a series of beautifully made cells, for the protection of the future brood.
Turn we first to some exotic Ants which inhabit tropical America.
I have felt considerable doubt whether the SAÜBA, or COUSHIE Ant (Œcodoma cephalotes), ought to be reckoned among the burrowers or the builders, inasmuch as it makes large excavations below the ground, and raises dome-like edifices on its surface. As, however, the burrows are very much larger than the buildings, I shall place it with the former class, reserving for the corresponding example of the building-insects the Termites, whose edifices are more important than their burrows. It must first be mentioned that, although this species has often been described as the Visiting Ant, it is in reality a distinct species, as will be seen in the course of a few pages.