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Those animals, which by their size chiefly attract our attention, are but the smallest part of animated nature: the whole earth swarms with living beings: every plant, every grain and leaf, supports the life of thousands. Vegetables seem, at first sight, to be the parts of organized nature which are produced in the greatest abundance; but upon minuter inspection, we shalì find each supporting numberless minute creatures, who fill up the various gradations of youth, vigor, and old age, in the space of a few days' existence.

Vegetables are generally produced but once in a season; but among insects, especially of the smaller kinds, a single summer suffices for several generations. These, therefore, would multiply in a greater abundance than the plants on which they subsist, but that they are destroyed by other animals, and often by each other the spider feeds on the fly; the birds upon the spiders; and they, in turn, make the food of man and every beast of prey.

Some insects as to their conformation are composed of several rings, joined together by a membrane, which is the usual form of the body in grubs, worms, and caterpillars. Unlike birds, who traverse the air with such rapidity, these humble animals, seemingly less favorites of nature, move forward but slowly. The whole body consists of a chain of annular muscles, whose orbicular fibres being contracted, render one of the rings that was before ample and dilated narrow and long. The fibres of these rings are found to be spiral, as are their motions in a great measure, so that by this means they can the better bore their passage into the earth. Their crawling motion may be explained by a wire wound round a walking-cane, which when slipped off, and at tempted to be lengthened, has an elastic contraction of one ring

to the other. In like manner the earthworm, having shot out or extended its body, lays hold upon some substance with its small feet, and so brings onward the hinder part of its body.

Caterpillars have feet both before and behind, which not only enable them to move forward by a sort of steps made by their fore and hinder parts, but also to climb up vegetables, and to stretch themselves out from the boughs and stalks to reach food at a distance. Behind, their broad palms are beset almost round with sharp small nails, to hold and grasp whatever they are upon; likewise before, their feet are sharp and crooked, by which they can lay hold of leaves, while their hinder parts are brought up thereto. Reptiles that have many feet may be observed to move them regularly one after another, and from one end of the body to another, in such a manner that their legs in walking make a sort of undulation; and by this means they move much swifter than one would imagine. The motion of snails is performed in a different manner; they have a broad skin along each side of the belly, which has an undulating motion, by which, with the help of the slime that covers their bodies, they can move slowly forward, and adhere to every surface at pleasure.

The second sort of insects are flies of various kinds, whose bodies are covered by small plates, not unlike our ancient armor, the pieces of which are lengthened by unfolding, and shortened by running over each other. These lead a more luxurious life, transfer themselves from place to place with rapidity, and spend their little existence in feasting and propagating their kind.

The third sort are ants, spiders, and others, whose bodies are divided into two or three portions, joined by a sort of ligament. Of all the race of reptiles these seem to be endowed with the greatest share of sagacity. The wisdom of the ant, and its wellformed commonwealth, are too well known to be insisted on; but the spider, though it leads a solitary and rapacious life, seems

endowed with even superior instincts. Its various artifices to ensnare its prey, and, when no longer able to supply a new web itself, the stratagem it lays to get possession of that belonging to another, are evidences of its cunning.

The minuteness of insects may render them contemptible in the eyes of the unthinking; but when we consider the art and mechanism in so minute a structure, the fluids circulating in vessels so small as to escape the sight, the beauty of their wings and covering, and the manner in which each is adapted for procuring its peculiar pleasures, we shall find how little difference there is between the great and the little things of this life, since the Maker of all has bestowed the same contrivance in the formation of the elephant and the ant.

The structure of the eye in insects is remarkably different from that of other creatures in several respects. It is defended by its own hardness against external injuries, and its cornea, or outer coat, is all over divided into lenticular facets, and through the microscope appears as a beautiful piece of lattice work. Each hole in this is of such a nature, that when looked through every object seems inverted. This mechanism alone supplies the place of the crystalline humor, which is not to be found in insects. Spiders have generally eight eyes, and flies may be said to have as many as there are perforations in the corOther creatures are obliged to turn their eyes different ways to behold objects, but flies have them so contrived as to take in every object near them at once. In order to keep their eyes clean, they are provided with two antennæ, or feelers. Some, however, are of opinion, that they clean their eyes with their fore legs as well as the feelers; nor is this conjecture ill founded, when we consider, that in some sorts, particularly the flesh-fly, the feelers are too short for this purpose, and therefore their legs alone can supply the defect.

nea.

The mechanism in the feet of flies, and other insects, deserves also our notice. The amphibious insects, which are obliged to live by land as well as water, have their hindmost legs made with commodious flat joints, having gristles on each side serving for oars to swim with, and placed at the extremity of the limb; but nearer the body there are two stiff supporters to enable them to walk when they have occasion. In those insects whose motions are performed by leaping, such as the grasshopper and cricket, their thighs are strong and brawny; those, on the contrary, which use their claws in perforating the earth, have such parts made with strength and sharpness, as in the wild bee, and the beetle. There are even some animals that convey themselves by methods to us unknown. Insects, which are generated in stagnant waters, are often found in new pits and ponds, and sometimes on the tops of houses and steeples. Spiders with their webs have been known to soar to a considerable height, having been seen above the highest steeple of York Minster. How these animals have been thus capable of conveying themselves from place to place is a phenomenon for which we are unable to account. Some years ago, it was the method to give reasons for every appearance in nature, but as philosophy grows more mature it becomes more cautious and diffident, nor blushes in many instances to avow its ignorance.

Those insects which are provided with wings have tendons, which distend and strengthen them; those which are provided with four, use the outermost rather as cases to defend the internal wings than as instruments in flying. When the insect is at rest, the inner wings are generally gathered up in the manner we close a fan, nor is it without some efforts that the little animal can unfold it. Those, however, whose wings are not cased in this manner, such as moths and butterflies, have them defended with feathers; for that beautiful variety of colors which we so

much admire, appears, through a microscope, to be nothing more than different colored plumage, as artfully placed as in the wings of birds, but too minute to be discerned by the naked eye. Such insects as have but two wings have two little balls, or poisers, joined to the body under the hinder part of each wing, that serve to keep them steady, and in some measure counteract the changes of the air, which might at every variation carry them in its current. If one of these poisers be cut off the insect will soon fall to the ground; but if they are both cut, it will still fly, but yet in the direction of every breeze.

They are thus formed for motion, rather to provide sustenance than to avoid danger. As from their natural weakness they are the prey of every superior order of animals, they seem to find safety only in their minuteness or retirement ; but even with every precaution they furnish out a repast to swallows and other birds, who, while to us they seem sporting in the air, arc then employed in procuring their necessary subsistence. The insect itself, however, is at the same time in pursuit of some inferior order of insects; for there are the same hostilities among the smallest that there are among the largest animals.

Summer is the season of their pleasures; many of them never live above a single season, while others are found to continue but one day. Such however as are more long-lived, take the proper precautions to provide for their safety in winter, and fix upon the most convenient situations for spending that interval, and such as want food lay in the proper stores for subsistence. But the greatest number want no such necessary stock, for they sleep during the continuance of the winter. Some caterpillars, for instance, having fed during the summer, retire, at the approach of cold, to a place of safety, and there, by spinning a thread like a cobweb, hang themselves in some commodious place, covered with a factitious coat, which at once serves to keep them warm, and guard

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