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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 semi-circular, 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 bevelled off inwards, 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. Towards 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 SAUBA ANT and its habitation-Use of the "parasol" leaves-Mr. Bates account of the insect-Enormous extent of the Dwelling-The DUSKY ANTIts 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 Antenna-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 Colours, Disposition and Habits-The WASPIts 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 Travellers-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 entirely 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 colours, 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 Mayfly, 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 marvellous 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 revelled 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, sawflies, 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 (Ecodoma 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.

The Sauba Ant is restricted to tropical America, where it exists in such vast profusion, that it oftentimes takes forcible possession of the land, and drives out the human inhabitants who have cultivated and planted it. Broad columns of these ants may be seen marching along, each individual carrying in its jaws a circular piece of leaf, about the size of a sixpence, which is held vertically by one of its edges. In the British Museum there is a specimen of a Saüba Ant, with the leaf still grasped in its jaws, the ruling passion strong in death. From this curious habit the creature is sometimes called the Parasol Ant, and many persors have thought that the leaves are carried in order to protect the insect against the hot sunbeams. The real reason, however, has been discovered by Mr. H. W. Bates, who has studied with great care the habits of this remarkable insect, and has disentangled its history from many doubts and difficulties.

There are, as is usual with all ants, three distinct ranks —namely, the winged, the large-headed, or soldiers, as they are popularly called, and the ordinary workers. The large-headed individuals are sub-divided into two classes, namely, the smooth

heads and rough-heads, the former wearing a polished, horny, translucent helmet, and the head of the latter being opaque and covered with hair. The large-headed ants do no ostensible work, all the labour falling to the lot of the workers. These creatures make raids upon the trees, always giving the preference to cultivated trees, such as the orange and the coffee, and cut away the leaves so fast that the growth is stopped, and the entire plant sometimes dies.

The use of the leaves is to thatch the domes of their curious edifices, and to prevent the loose earth from falling in. Some of these domes are of gigantic dimensions, measuring two feet in height and forty feet in diameter, the mightiest efforts of man. appearing small and insignificant when the comparative dimensions of the builders are taken into consideration. Division of labour is carried out to a wonderful extent in these buildings, for the labourers which gather and fetch the leaves do not place them, but merely fling them down on the ground, and leave them to a relay of workers, who lay them in their proper order. As soon as they have been properly arranged, they are covered with little globules of earth, and in a very short time they are quite hidden by their earthy covering.

The functions performed by the large-headed ants are not very evident. Those with smooth fronts seem to do nothing but walk about. They do not fight like the soldier-termites, nor do they appear to exercise any rule over the workers. Moreover, they have no sting, and even when assaulted they scarcely ever resent the insult. The hairy-headed variety is still more enigmatical in its duties. "If the top of a small, fresh hillock, one in which the thatching process is going on, be taken off, a broad cylindrical shaft is disclosed, at a depth of about two feet from the surface. If this be probed with a stick, which may be done to the extent of three or four feet without touching the bottom, a sinal number of colossal fellows will slowly begin to make their way up the smooth sides of the mine. Their heads are of the same size as the class No. 2, but the front is clothed with hairs instead of being polished, and they have in the middle of the forehead a twin ocellus, or simple eye, of quite different structure from the ordinary compound eyes on the sides of the head. This frontal eye is totally wanting in the other workers, and is not known in any other kind of ant. The apparition of

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