head; and, by strong efforts, soon afterwards push it entirely off. In their chrysalid state they remain for some time, to all appearance, perfectly inanimate; but this is only in appearance, for, on being taken into the hand, they will always be found to exhibit signs of life. It is singular that, in the changes of insects, the intestinal canal is frequently very dif ferent in the same individuals, as they pass through their three states. In the larva this is composed of two principal tubes, the one inserted into the other : the external tube is compact and fleshy, and the internal one thin and transparent. The latter is always thrown out of the body previously to the transformation.

As soon as the parts of the animal, within the shell of the chrysalis, have acquired strength sufficient to break the bonds that surround it, the little creature exerts its powers, and appears to the world in its perfect state. For a little while it continues humid and weak; but, as the humidity evaporates, its wings and shell become hardened, and it soon afterwards commits itself in, safety to its new element.

From the metamorphosis of insects I shall proceed to the examination of some of their more important members, as observed in the perfect state of the animals.

Some writers have conjectured that the antenna or borns of insects were their organs of hearing; for it is evident, from various experiments, that insects are possessed of this sense in a degree as exquisite as most other animals, although, from their minuteness,

we perhaps may never discover by what means. The antennæ, however, seem little likely to answer the purpose of cars. These instraments, of apparently exquisite sensibility, scem adapted to very different purposes, but to purposes with which we may remain long unacquainted.

The eyes are formed of a transparent crustaceous set of lenses, so sufficiently hard as to require no coverings to protect them. These, like multiplying glasses, have innumerable surfaces, on every one of which the objects are distinctly formed; so that, if a candle is held opposite to them, it appears multiplied almost to infinity on their surfaces. Other creatures are obliged to turn their eyes; but insects have always some or other of these lenses directed towards objects, from what quarter soever they present themselves. All these minute hemispheres are real eyes, through which every thing appears topsyturvy.

Mr. Leeuwenhock looked through the eye of a Dragon-fly (with the help of a microscope) as a telescope; and viewed the steeple of a church, which was 299 feet high, and 750 from the place; he could plainly see the steeple, though not apparently larger than the point of a fine needle. He also viewed a house; and could discern the front, distinguish the doors and windows, and perceive whether the windows were open or shut. Mr. Hook computed 14,000 lenses in the two eyes of a drone. Mr. Leeuwenhoek reckons in each eye of the Dragon-fly 12,544 lenses. The pictures of objects, therefore, that are delineated on these, must be millions of

times less than those formed on the human eye. Many insects still smaller have eyes, no doubt contrived so as to discern objects some thousands of times less than themselves; for such the minute particles on which they feed must certainly be. How astonishing, therefore, must be the magnifying power of such eyes! And what extraordinary discoveries might be made, were it possible to obtain glasses through which we could see as these little creatures do!

With respect to the wings of insects, the two first orders of Linnæus have theirs defended by a pair of crustaceous cases called elytra. The three subsequent orders have four membranaceous wings, without elytra. All the insects of the sixth order have but two wings, and under each of these, at its base, there is a poise or balancer like a little knob. These poises are commonly little balls, placed on the top of a slender stalk, and moveable every way at pleasure. In some they stand alone, but in others, as in the whole Flesh-fly tribe, they have little covers or hollow membranaceous scales, each of which somewhat resembles a spoon without a handle: every time the insect strikes the air with its wings, a very quick motion may be perceived in the balancer; and in the Flesh-flies, when this moves, it strikes against the little scale, and thus assists in producing the wellknown buzzing sound that is made by flics when on the wing. The use of the balancers to an insect seems to be precisely the same as that of a long pole, loaded at each end with lead, is to a rope-dancer!

they render the body steady, and obviate all its vacillations in flight. If one of them be cut off, the insect will immediately fly ill, one side evidently overbalancing the other, till it falls to the ground: if both be cut off, it will fly very awkwardly and unsteadily, exhibiting an evident defect of some necessary part.

The structure of the feet of these diminutive creatures is truly admirable. Those insects that live. altogether in water have their feet long, flat, and somewhat hairy at the edges, well adapted to aid their motions in that element. Such as have occasion to burrow into the earth have their legs broad, sharp-edged, and serrated. Those that use their feet only in walking have them long, and cylindrical; some of the feet are furnished with sharp hooked claws, and skinny palms, by which, from the pressure of the atmosphere upon them, the insects are enabled to walk on glass and other smooth surfaces, even with their backs downwards, as in various species of flies: others have somewhat like spunges that answer the same end: and the spider has each foot armed with a kind of comb, probably for the purpose of separating the six threads that issue from so many orifices of its body, and prevent them from tangling. In the hind legs of insects which have occasionally to pass over spaces by leaping, the thigh is very large and thick, and the shank long and fre quently arched.

From the different formations of these, it is not difficult to recognize the habits and modes of life

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of insects, even where the specimens exhibited happen to be dead. The relative proportions of the feet determine, in a certain degree, the manner of each insect's motion in walking. Those species that have long legs (generally speaking) run very quickly, as the Spiders, the Long-legged Spiders, and several kinds of Beetles. On the contrary, the insects that have short legs, as the Julus, Ticks, and Gall Insects, are generally remarkable for the slowness of their pace. When the anterior feet are the longest, they retard the motion: this takes place in the Ephemera, Mantis, and some others: the feet of these insects are of little other use to them than in enabling them to lay hold of any body on which they wish to alight. The posterior legs, being longest, give to the insects the faculty of leaping. Some insects however leap, whose posterior legs are not longer than the others; but they have this faculty in consequence of the thighs being very thick, and furnished with particular muscles.

The tongue of insects is a taper and compact instru ment, by which they suck their food. Some of the animals can contract or expand it; and others, as the Butterflies, roll it up under their head, somewhat like the spring of a watch. In many it is enclosed within a sheath; and in several, as the flies, it is fleshy and tubular,

· The mouth is generally placed somewhat underneath the front part of the head; but in a few of the tribes it is situated below the breast. Some insects have it furnished with a kind of forceps, for the purpose of