skin; that skin, however, with its appendant legs and hooks, the chrysalis must cast off; but, although destitute of limbs or hooks, it yet contrives to fix itself on the same cone to which the caterpillar was attached. When the skin has been well thrust down, the insect seizes some part of it in one of the indentations between two of the rings of its body: this secures a resting place, which enables it to withdraw its tail altogether from the old skin.

Wholly freed from its former covering, the chrysalis is now attached to a frail and withered slough, and suspended in mid-air in a situation of great peril. It becomes now indispensable that it should fix itself to the silken cone. But to a creature hanging with its head downwards, and destitute of limbs, this would seem a hopeless undertaking. Destitute and helpless, however, as its condition appears, nature has not left it without adequate resources. It elongates that part of the body which is above the rings, by which it holds on, and seizes by the interval between two rings still higher than those, another part of its caterpillar skin. Having in this manner advanced by three or four steps to the required height, it feels

about with its tail for the silken cone. Having at last found this cone, it fixes itself to it by means of hooks with which that part of its body is furnished.

To withdraw the tail from the withered case; to climb up that case, and hook its body to the silken cone, is an operation so delicate and hazardous as to excite the greatest wonder, that an insect which executes it only once during the whole term of its existence, should be found capable of executing it so well. Assuredly," says Reaumur," it must have been taught to perform its task by some great master.”

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But the chrysalis does not seem to be content with merely withdrawing itself from its ancient hide: it will not suffer it to remain suspended in its own neighbourhood. In order to rid itself of the annoyance of the offensive slough, it bends a section of the lower part of its body into the form of the letter S, and

then gives the whole a jerk, which causes both its own body and the attached slough to spin round eighteen or twenty times on their axis. As the slough and chry salis must necessarily go round together, and as the slough is farther than the chrysalis from the centre of gyration, it is evident that the attaching hooks and

threads of the slough must suffer a greater strain than those of the chrysalis: consequently the former give way first. This is no sooner perceived by the chrysalis, than it resumes its vertical position, and allows the skin to drop. If the first series of pirouettes prove unsuccessful, the chrysalis tries another in the contrary direction; and if after repeated efforts it fails to get rid of the nuisance, it calmly and patiently submits to an evil which it cannot remove.

This vertical position does not however suit all caterpillars; there are some which fix themselves in an inclined or even horizontal position. To effect this, a set of threads is passed round their bodies, and then attached to the wall or a part of some plant from which they remain suspended.

These girths or supporting belts are formed in various ways, but always of the same material,-silk spun for that purpose by the caterpillars. The following figures will explain some of those processes by which the suspension is effected. In the first figure, (fig. 1,) the caterpillar is seen to bend its body to the point where the end of the thread is to be fixed: in the

second, (fig. 2,) it presents itself in the act of carrying over the body, by doubling itself on its back: while in the third, (fig. 3,) it appears to turn round for the pur

pose of fixing it on the further side. When a sufficient number of threads have been thus spun to form its web, the insect gently withdraws its head, assumes a straight position, and quietly awaits the hour of its transformation.

The girth which is passed round the body of the caterpillar in order to suspend it when it shall have assumed the chrysalid form, is fabricated sometimes in the mode represented in the annexed figures. On one

side of a stalk or leaf, it glues some of the viscid matter secreted by its spinner; it then gradually brings its head into a position which enables it to pass the silken cord from a to b where it is supported by one of its legs; introducing the two other legs of that side under the rest; the insect then carries it from b to c: it is then continued from c to d, which completes the loop, or half circle. When a sufficient number of threads has been thus passed from a to d, the loop has acquired a requisite strength:-the insect then holds it up with its two fore legs: bending its head between these legs, it passes the loop over its back; and by the action of the rings, it gradually brings it to that part of the body which is best calculated to balance the chrysalis.

In spite, however, of all the care which the insect

takes to sustain the loop, it occasionally happens that the threads slip off its legs and fall. This is a woful calamity to the unhappy caterpillar. It does its best to repair the damage; with marvellous patience it endeavours to collect the scattered filaments, and secure them once more between its legs. One unlucky insect was seen by Reaumur, trying every contortion of limb to effect this purpose, but all in vain. After all its exertion, it only succeeded in gathering about half the number of threads which had formed the cord, the rest having become hopelessly entangled; and being either unwilling or unable to spin an additional supply, it suspended itself by this imperfect girdle. As it might have been anticipated, the suspending girdle proving too weak to sustain the motions of the chrysalis, gave way, and the miserable insect consequently fell to the ground and perished.

If we open one of these chrysalis or aurelias, from which a brilliant butterfly will emerge at the proper season, all we shall be able to discover, especially at first, is a mass of pap or soft substance apparently putrified, in which every thing seems confounded; but this soft mass, however confused it may appear to the eye, contains the elements of the future insect. Under the action of heat, the superfluous portion of the nutrimental substances gradually transpires through the film which encloses them; the external film itself becomes by degrees tinctured by a most beautiful vermilion, and the limbs and features, which at first lay concealed in the mass, begin to disengage themselves from the case which contained them, and which now bursts open then it is that the head unfolds itself to our view, the horns and legs lengthen, the wings ex