and then, by turning itself round, it presses against the sides, which renders them smooth and firm. The dome, or covering, is formed in the same way; earth is collected on the foot, which it then turns upward, and throws off by exuding fresh mucus; and this is repeated, till a perfect roof is formed. Having now completed its winter house, it draws in its foot, covering it with the mantle, and opens its spiracle to draw in the air. On closing this, it forms, with its slime, a fine membrane, interposed between the mantle and extraneous substances. Soon afterwards, the mantle secretes a large portion of very white fluid over its whole surface, which instantly sets uniformly, and forms a kind of solid operculum, like plaster of Paris, about half a line in thickness, which accurately closes the mouth. When this is become hard, the animal separates the mantle from it. After a time, expelling a portion of the air it had inspired, and thus being reduced in bulk, it retreats a little farther into the shell, when it forms another leaf of mucus; and it continues repeating this operation, till there are sometimes five or six of these leaves, forming cells filled with air between it and the operculum. Respiration ceases during the period of hybernation.*

The mode in which these animals escape from their winter confinement is singular:-The air which they had expired, on retiring into their shell farther and farther, remains between the different partitions of the mucus membrane above mentioned, which forms so many shells hermetically sealed; this they again inspire, and thus acquiring fresh vigour, each separate partition, as they proceed, is broken by the pressure of the foot, projected in part through the mantle; -when arrived at the operculum, they burst in by a strong effort, and finally detaching it, then emerge, begin to walk, and to break their long fast!

'In all these proceedings,' observes Mr. Kirby, after recording the above details, the superintending care and wise provisions of a Father-Being are evident. This creature can

* Goldsmith is mistaken when he says, that the snail opens an airhole into its shell.-Gaspard and Bell; Zoological Journal, i. 93; ii. 174.

neither foresee the degree of cold to which it may be exposed in its state of hybernation, nor know by what means it may secure itself from the fatal effects it would produce upon it, if not provided against.

'But, at a destined period, often when the range of the thermometer is high, not stimulated by a cold atmosphere, except perhaps by the increasing length of the night,-at the bidding of some secret power, it sets about erecting its winter dwelling; and, employing its foot, not only as a shovel to make its mortar, but as a hod to transport it, and a trowel to spread it duly and evenly, at length finishes and covers in its snug and warm retreat; and then, still farther to secure itself from the action of the atmosphere, with the slimy secretion with which its Maker has gifted it, fixes partition after partition, and fills each cell, formed by it, with air, till it has retreated as far as it can from every closed orifice of its shell, and thus barricades itself against a frozen death. Again, in the spring, when the word is spoken,—Awake thou that sleepest, it begins immediately to act with energy; it re-inspires, as above related, the air stored in its cells; bursts all its cerements; returns to its summer haunts, and again lays waste our gardens.'*

SEVENTH WEEK-SATURDAY.

HYBERNATION OF THE BEETLE.-ANIMALCULES IN PASTE.

AMONG insects, the beetle has some peculiar instincts which will come more properly under our observation at another season. At present, I shall only mention three instances of remarkable habits relating to the state of particular species of this insect in winter. Beetles, it may be premised, are distinguished from other tribes of the same order, by being furnished with cases to cover two transparent wings. Like other insects, they are bred from eggs, which first become

* Kirby's Bridgewater Treatise, pp. 285-289.

grubs; then chrysalides, in which parts of the future fly are distinctly seen; and, lastly, assuming their perfect or imago state, they acquire wings, and mount into the air.

The first species of this little animal which I shall introduce to the notice of my readers, is the May-bug, or Dorrbeetle, well known to children by its evening buzz during the months of summer. In its maggot state, in which it remains, without any other change than increase of size and the annual renewal of its skin, for no less a period than three years, it burrows under ground, so near the surface as to devour the roots of plants, on which it feeds voraciously, and without discrimination. When largest, it is found an inch and a half long, of a whitish-yellow colour, with a body consisting of twelve segment or joints, on each side of which there are nine breathing holes, and three red feet; but it is destitute of eyes, having no occasion for them in its natural habitation, where light does not penetrate,-here exhibiting a new and remarkable instance of the attention of the Creator, in adapting the faculties of creatures to the situation for which they are destined, as well in what he withholds as in what he grants.

Towards the conclusion of the fourth year of its existence, it begins to provide itself a secure winter habitation, with a view to its future condition. About the latter end of August, it seems first to come under the influence of that extraordinary instinct, which leads it to prepare for its important change. It then buries itself deeper and deeper in the earth, sometimes, in favourable situations, to the depth of six feet, and there forms for itself a capacious apartment, the walls of which it renders very smooth and shining, by the exertions of its body. Its abode being thus formed, it begins soon after to shorten itself, to swell, and to burst its last skin, in order to assume the form of a chrysalis. This, in the beginning, appears of a yellowish colour, which heightens by degrees, till at last it appears nearly red. Its exterior form plainly discovers all the vestiges of the future winged insect,

the entire fore-parts being distinctly seen; while, behind, the animal seems as if wrapped in swaddling-clothes.

The young May-bug continues in this state for nearly three months, and then divests itself of all its impediments, and becomes a winged insect, completely formed. This happens about the beginning of the year; but it is not yet time for it to emerge into open day, the season of the year being unpropitious to its new habits. Unlike most other insects, therefore, which, immediately after their change, enter at once into all the enjoyments of their new being, it remains in a state of infant imbecility for four months longer, during which time, though without food, it gradually acquires firmness and vigour; and, about the end of May, when the genial season has returned, it works its way to the light and warmth of the summer's atmosphere, where, after living for four years under ground, and feeding only on roots, it enters on the delights of its nobler existence, buzzing joyfully through the mild air, having the sweetest vegetables for its banquet, and the dew of evening for its drink.

Another insect, allied to the beetle kind, is still more remarkable in its instincts, if any thing in this world of wonders can be said to have the pre-eminence,-I allude to the nut-weavil (Curculio bucum). Dr. Good has chosen this little creature as an illustration of the absurdity of the hypothesis, which makes instinct to depend on imitation, education, or reasoning; and, assuredly, even though the supposition were not contradicted by almost every habit and pursuit of the inferior creation, this instance might of itself be sufficient to show the untenable nature of the theory. The nut-weavil, 'with a finished knowledge of the art,' as Dr. Good expresses it, singles out a nut in the month of August, while its shell is yet soft and penetrable; and, having prepared to deposit her eggs, pierces it with her proboscis, and then, turning round accurately, drops an egg into the minute perforation. Having accomplished this, she passes on, pierces another nut, drops another egg, and so continues, till she has exhausted her whole stock. The nut continues to grow; the egg is

soon hatched; the young maggot finds its food already ripened, and in waiting for it. About the time of its full growth, it falls with the mature nut to the ground, and at length, when its provision here is exhausted, creeps out, by gnawing a circular hole in its side. It then burrows under the surface of the ground, where it continues dormant for eight months, at the termination of which it casts its skin, becomes a chrysalis of the general shape and appearance of the beetle kind; and in the beginning of August throws off the chrysalid investment, creeps to the surface of the ground, finds itself accommodated with wings, becomes an inhabitant of the air, and instantly pursues the very same train of actions, to provide for a new progeny, which had been pursued by the parent insect of the year before.'

One more example which I shall notice, of the habits of particular species of the remarkably varied class of beetles, is of a very different kind; and my object in adverting to it, is to show another principle, by which the sterility of winter is rendered innoxious to certain animals. We have seen instances in which, among vertebrated as well as invertebrated beings, the expedient of torpidity is resorted to by the Author of Nature, to sustain life, and perhaps enjoyment also, during this rigorous season. But, in the example I am going to produce, there appears to be no need of this suspension of motion and external sensation, as the little creature is able to survive a whole winter, and even much longer, without any food whatever, except what is derived from the atmosphere; and this, indeed, is a property which belongs to various classes of the invertebrated genus. The account is taken from the communication of a writer in the Philosophical Transactions:"On the removal of a large leaden cistern, I observed at the bottom of it black beetles. One of the largest I threw into a cup of spirits,-it being the way of killing and preparing insects for my purpose. In a few minutes it appeared to be quite dead. I then shut it up in a box, about an inch and a half in diameter, and, throwing it into a drawer, thought no more of it for two months; when, opening the box, I found it