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Obs.- Pearls are found in oysters and muscles. They are ealcareous concretions, formed of the liquid of which the inner surface of the shell 18 composed, and are an effect of accidental injury to the shell. The Chinese increase the number of pearls, by catching muscles and perforating the shells; and then replace the muscles in the water. After a certain time, on opening them again, they discover pearls attached to the part injured. The substance of the shells of these animals, when chemically examined, is found to be a mild calcareous earth, deposited in a mass of net work, composed of animal matter. The shining matter, left in the tracks of snails, is this very substance; which, when deposited in strata above one another, hardens and forms a shell.

2. Many hundreds of unknown species of mineral sbells are found in the strata of the earth, the remains of seas and shores now no more.

508. The polype is an insect of a snail or jelly-like substance. It shrinks into a round green spot, if disturbed; but, in its natural form, is a long tube, and has a head and mouth, from which eight or ten long arms are projected to seize worms and other insects.

The young issue from its side in a surprising manner; but, it is the wonderful property of this insect, that if cut into any number of pieces, and in any direction, each part will become a perfect polype in itself!

It may may even be turned inside out without injury; and the dismembered parts of one polype will unite with those of another, and make one perfect polype !

509. After a man has exerted his eyes to view the smallest insect, he will find, on applying a microscope, others so small, that ten thousand of them are not equal in bulk to the smallest which he can view with his naked eye.

Lewenhoeck tells us of insects, seen with a microscope, of which 27 millions would only be equal to a mite, and four millions to a single grain of sand.

510. Yet each of these animalculæ has an organized body, provided with a heart, lungs, muscles, glands, arteries, and veins; and with blood and other fluids passing through them!

Their vigour and powers of action are generally superior even to those of larger animals; their length of life is also great in proportion to their size.

The mite makes 500 steps in a second ; animalçules, in a drop of water, swim about with as much freedom as a whale in the sea ; and those that feed on the leaves of trees resemble oxen grazing in large pastures.

Wak'd by his warmer ray, the reptile young
Come wing'd abroad; by the light air upborne,
Lighter, and full of soul. From every chink,
And secret corner, where they slept away
The wintry storms; or rising from their tombs,
To higher life; by myriads, forth at once,


Swarming, they pour : of all the varied hues,
Their beauty-beaming parent can disclose.
Ten thousand forms, ten thousand different tribes
People the blaze! To sunny waters some,
By fatal instinct fly: where on the pool,
They, sportive wheel; or, sailing down the stream
Are snatch'd immediate by the quick-eyed trout,
Or darting salmon. Through the greenwood glade
Some love to stray : there lodg'd, amus'd, and fed,
In the fresh leaf. Luxurious, others make
The meads their choice, and visit every flower,
And every latent herb: for the sweet task,

propagate their kinds, and where to wrap,
In what soft beds their young, yet undisclos'd,
Employs their tender care. Some to the house,
The fold, and dairy, hungry, bend their flight:
Sip round the pail, or taste the curdling cheese
Oft, inadvertent, from the milky stream
They meet their fate: or, weltering in the bowl,
With powerless wings, around them wrapt, expire.

511. Animalcules are shaped like fish, reptiles, eels, stars, hexagons, triangles, ovals, and circles; they have horns, probosces, &c. and although the eyes of many species are not discernible, yet they move abı ut with inconceivable relative velocity in the fluids they inhabit, without interfering with each other.

512. Hunter divided all animated nature into single and complicated animals. The single, are those which possess only feeling or the powers of muscular contraction, and the power of absorbing food, as chalk absorbs moisture, and appropriating it to nourishment.

The Hydatid, found in sheep, consists only of a bag filled with water, and has no appearance of animal powers; but, when excited or pricked, contracts and shews its irratibility; while this vital power is sup: ported by the nourishment which it receives through its coat.

513. From such simple animals, we ascend, through all the degrees, up to the complicated and combined powers of body and mind, in MAN!

The links are kept up, by the addition of muscles, for additional motions; by other senses, for hearing, seeing, &c. and by various degrees of irratibility in those senses.

The blood for renovation circulates through the lungs; and for action through the muscles of the heart; secretions take place by the various glands; the contraction of the muscles moves the bones; the nerves convey the effect of the mental secretions to the brain ; and there produce the inscrutable powers of sensation, will, and judgment.

514. Although animals, in general, are sufficiently distinct from vegetables, yet the gradations of nature are so minute, that many animals are but slightly removed from vegetables, having not more than one or two senses; and, as in some shell-fish, have not even the power of loco-motion.

Between these and man, there is a regular succession of that cunning and sagacity which are necessary to preserve and sustain life; yet between man and most other animals, there is, in mental capacity, as great a difference as between some of those and vegetables.

Far as creation's ample range extends,
The scale of sensual, mental powers, ascende:
Mark, how it mounts to man's imperiał race,
From the green myriads in the peopled grass :
What modes of sight, betwixt each wide extreme,
The mole's diui curtain, and the lynx's beam;
Of smell, the headlong lioness between,
And bound sagacious, on the tainted green:
Of hearing, from the life that fills the flood,
To that which warbles thro' the vernal wood!
The spider's touch, how exquisitely fine!
Feels at each thread, and lives along the line :
In the nice bee, what sense so subtly true!
From poisonous herbs extracts the healing dew:
How instinct varies in the grovelling swine,
Compar'd, half-reasoning elephant, with thine !
"Twixt that, and reason, what a nice barrier:
For ever separate,- yet for ever near! POPE.

Seven remarkable specimens of Animated Nature.


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