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until the complete figure, so exactly conceived beforehand, assigned, and provided, grows into its last perfection, and emerges, like a new creation, into its aerial and beautiful proportions.

It seems like a resurrection from the tomb to a fresh life, with celestial destinations. It is so analogous to that which the human spirit is appointed to undergo, that the intellect cannot well avoid viewing the insect transformation as the emblem, the token, the natural herald and promise of our own. The ancients, without our Christian revelation, thought so; for one of their most pleasing imaginations, yet visible on some of their gravestones which we dig up, is that of a butterfly over the name or the inscription which is recorded. They place the insect there as the representation of their Psyche — of the animating and surviving soul; as the intimation that it will reappear in a new form and region of being. The allusion and the applicability are so striking, that we cannot but believe that one of the great purposes of the Deity in creating his insect kingdom was to excite this sentiment in the human heart.

The fly passes through such changes to its winged state. So does the gnat, that is so annoying to us. And the little maggot, that we meet with in the nuts we open, undergoes, if undisturbed, a like transformation. These successive states of insects, after the egg, are usually called the larva, the pupa, and the imago. Most, in the second, the pupa or chrysalis stage, never eat; but several species continue to move and feed.

The habits and actions of the insect world display the same kind of animal mind and feeling which birds and quadrupeds exhibit. Bees, wasps, and especially ants, give manifestations of intelligence and a contriving instinct, which bring them earer to mankind than any other class of animated nature. Many insects show as much maternal care in depositing their eggs as fishes and oviparous quadrupeds. The white butterfly roves till she finds the proper cabbage plant, in which she

may lay her burden most fitly for its welfare. The dragon. fly seeks the water, as the most proper for her brood; and the earwig, like the fowl, sits and hatches its young.

That the mason wasp, when she deposits her eggs, should also seek and place in the same hole enough grubs to be the food of her young ones when they leave the shell, announces a parental foresight which no fish or oviparous animal has been found to equal. But that another kind of the same wasp should not only add this supply, but also, about the time when the new brood must be in life, and must have consumed it, should open their cell, and put into it another grub for their nutrition, and should repeat this till they are fit to provide for themselves, and that others should, in like manner, provide a succession of flies for their offspring while unable to help themselves, are circumstances which compel us to admit that insects have maternal instincts as completely as the hen, the cat, the lioness, or the bear.

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Insects have the senses of other animals, though varying in their modifications and acuteness. Their hearing has been questioned; but it seems certain that some, at least, possess this faculty. That spiders hear the sounds we make, and, when we make them the medium of our ideas, perceive our meaning in the sounds, and connect the same ideas with them, is evidenced by the fact of their coming for food when the musical notice is given to them. A man who was confined in the Bastile tamed a spider, and taught it to come for food at the sound of an instrument. And a manufacturer in Paris was in the habit of feeding several spiders in his apartment; so that whenever he entered, which he usually did with flies on a dish, they immediately came down to him, to receive their food. These instances imply memory, which many facts satisfactorily indicate. There seem to be reasonable grounds to infer that insects communicate their ideas and wishes to each other. Dr. Franklin inferred such a communication between ants, from a fact of his own observation. He found

some ants feasting on some treacle in his closet. He shook them out, and suspended the pot by a string from the ceiling. One ant had happened to remain, and, after eating its fill, found its way up the string with some difficulty, crawled on it to the ceiling, and thence along the wall to its nest. In less than half an hour a great company of ants sallied out of their hole to the ceiling, and crept along the string into the pot. This was done by others, till the treacle was all consumed; one body running up the string from the sweet, while another passed down to it. The doctor inferred that the first ant had communicated to its comrades the new position of their delicacy, and directed them to the only accessible road to it.

But the insect mind peculiarly displays itself, in some tribes, in the habitations which they build for themselves, and in those which they prepare for their young. The nests of birds, wonderful as they are, are eclipsed by the structures formed by many insects. The regular villages of the beaver, by far the most sagacious architect among quadrupeds, must yield the palm to a wasp's nest, and the spider galleries, with openings like doors, made to be as movable as any upon hinges, are not less ingenious. Very few insects, however, have been much studied; and it requires so long, persevering, and patient attention to perceive and understand their habits, that the intellectual principle of the insect world is very little understood.

LESSON LIII.

Birds. NUTTALL.

Of all the classes of animals by which we are surrounded in the ample field of nature, there are none more remarkable in their appearance and habits than the feathered inhabitants

of the air. They play around us like fairy spirits, elude approach in an element which defies our pursuit, soar out of sight in the yielding sky, journey over our heads in marshalled ranks, dart like meteors in the sunshine of summer, or, seeking the solitary recesses of the forest and the waters, they glide before us like beings of fancy. They diversify the still landscape with the most lively motion and beautiful association; they come and go with the change of the season, and as their actions are directed by an uncontrollable instinct of provident nature, they may be considered as concomitant with the beauty of the surrounding scene. With what grateful sensations do we involuntarily hail the arrival of these faithful messengers of spring and summer, after the lapse of the dreary winter which compelled them to forsake us for more favored climes!

If we draw a comparison between these inhabitants of the air and the earth, we shall perceive that, instead of the large head, formidable jaws armed with teeth, the capacious chest, wide shoulders, and muscular legs of the quadrupeds, they have bills, or pointed jaws destitute of teeth; a long and pliant neck, gently swelling shoulders, immovable vertebræ; the fore-arm attenuated to a point, and clothed with feathers, forming the expansive wing, and thus fitted for a different species of motion; likewise the wide-extended tail, to assist the general provision for buoyancy throughout the whole anatomical frame. For the same general purpose of lightness, exists the contrast of slender, bony legs and feet. So that, in short, we perceive, in the whole conformation of this interesting tribe, a structure wisely and curiously adapted for their destined motion through the air. Lightness and buoyancy appear in every part of the structure of birds; to this end nothing contributes more than the soft and delicate plumage with which they are so warmly clothed; and though the wings, or great organs of aerial motion by which they swim, as it were, in the atmosphere, are formed of such light materials, yet the force with which they strike the air is so great as to impel

their bodies with a rapidity unknown to the swiftest quadruped.

The same grand intention of forming a class of animals to move in the ambient desert they occupy above the earth, is likewise visible in their internal structure. Their bones are light and thin, and all the muscles diminutive, but those appropriated for moving the wings. The lungs are placed near to the backbone and ribs; and the air is not, as in other animals, merely confined to the pulmonary organs, but passes through, and is then conveyed into a number of membranous cells on either side the external region of the heart, communicating with others situated beneath the chest. In some birds these cells are continued down the wings, extending even to the pinions, bones of the thighs, and other parts of the body, which can be distended with air at the pleasure or necessity of the animal. This diffusion of air is not only intended to assist in lightening and elevating the body, but also appears necessary to prevent the stoppage or interruption of respira tion, which would otherwise follow the rapidity of their motion through the resisting atmosphere; and thus the ostrich, though deprived of the power of flight, runs almost with the swiftness of the wind, and requires, as he possesses, the usual resources of air conferred on other birds. Were it possible for man to move with the rapidity of a swallow, the resistance of the air, without some such peculiar provision as in birds, would quickly bring on suffocation.

Birds, as well as quadrupeds, may be generally distinguished into two great classes, from the food on which they are destined to subsist; and may, consequently, be termed carnivorous and granivorous. Some, also, hold a middle nature, or partake of both. The granivorous and herbiv orous birds are provided with larger and longer intestines than those of the carnivorous kinds. Their food, consisting chiefly of grain of various sorts, is conveyed whole into the craw or first stomach, where it is softened and acted upon by

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