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thing l'as been given by Providence for the purpose of destroying and counterbalancing them. Many species devour each other; and multitudes which might otherwise, by their numbers, become of serious injury to mankind, afford food to other creatures. The insect tribes increase with astonishing rapidity. The issue of some of them amount to more than two thonsand in a year; and, were these not destroyed by innumerable enemies, they would soon fill the air, and in the end would occasion the destruction of the whole animal and vegetable creation.

The offspring of every animal, with regard to number, bears a certain proportion to the duration of its life. The Elephant lives to the age of a hundred years or upwards; the female consequently produces but a single young one at a birth, and this does not arrive at maturity till it is sixteen or eighteen years old. Nearly the same may be remarked of the Rhinoceros, and of all the larger animals : but in most of the smaller ones, whose lives are short, or whose increase is not so injurious to man as the increase of these would be, we always find the number of offspring to be much greater. No species has ever been found to increase so much as to annihilate the others; and this singular harmony and just proportion has now been supported for several thousand years. Ove generation passeth away, and another succeedeth,” but all so equally as to balance the stock in all ages and in all countries.

In the Vegetable Creation we observe the same regularity as in Animals. There is scarcely a vegetable of any kind that is not rejected as food by some animals, and ardently desired by others. Numerous also are the plants which, at the same time that they afford only the natural nourishment to some, are, by others, cautiously shunned, as poisonous and destructive. All this has been contrived, by the Author of Nature, for the best and wisest purposes.

Every species of animal is admirably calculated for the climate in which it resides, and for its own peculiar mode of life. In the dreary northern regions, the dark animals become white, to evade, by their resemblance to the prevailing color of the country, the quick sight of their enemies. Their clothing, also, during winter, becomes nearly double what it is in the summer. In torrid climates the Sheep, as it is stated, loses his fleece, and is covered with hair. The Camel, that traverses the burning sands of the desert, is formed with soft, spongy feet, which the heat cannot crack : it has a reservoir of water, which enables it to resist for many days the attacks of thirst, in a country where water is not to be had; and it is contented with browsing on such miserable food as is to be met with in its progress. Innumerable other instances might be mentioned; but these are reserved for the body of the work.

In vegetables, we observe similar marks of superintendence. Some are alpine, and can exist only on the summits of mountains; some grow in marshes; others on the plains, &c; and each of these is exactly adapted to its peculiar situation. The plants of the desert are nearly all succulent, and able to bear the privation of mois. iure for an astonishing length of time. Those that are found on the sea-shore could not, in many instances, be retained in their situation, did not their roots become so matted among the sand, or strike so deeply down, as to render them immovable by all the shocks they sustain, either from the wind or water. It is also a remarkable circumstance, that Evergreens grow principally in the hottest climates, where they afford a natural shelter to the various animals, from the excessive heats to wbich they would otherwise be exposed.

If we attend to the contrivances of Providence for the preservation of animals during the winter of cold climates, we shall have an additional source of admiration. Most of those which feed on insects, either emigrate to other countries, or become torpid. Insects themselves, unable to bear the extreme cold, generally lie hidden within their cases, from which, at the approach of Spring, they burst and fly forth. Some animals, as the Beaver, Squirrels, &c , that feed on such vegetables as can be preserved through the winter, do not sleep, but live in their retreats on those provisions which their Creator has instructed them how to store up in the summer.

The preservation of the ffspring of all animals is not less wonderful than this. Quadrupeds are furnished with certain receptacles. in which is secreted a fluid called milk. With this their young ones are nourished till their stomachs are able to bear, and their teeth to chew, more solid food. As Birds are destitute of this species of nub triment, their offspring are able, as soon as hatched, to take into their stomachs such food as the parents collect for them; and the insect tribes are generally brought to life in a nidiis that itself affords them nourishment.

ON THE STUDY OF NATURE.

18

It is also deserving of remark, that birds of the same species always form their nests of similar materials, laid in the same order, and exactly of the same figure; 80 that. whenever a nest is seen, the bird that constructed it is immediately known. This is invariable in all birds and in all countries; with those taken, when just hatched, from the nest, and brought up in a cage, as well as with those that have all their lives been in a wild state.

From the animal we will once again turn to the vegetable kingdom, for the purpose of examining the contrivances of Nature there. If we look around us, wo shall find it a difficult matter to discover an entirely barren spot. If, by any devas. tation such be made, it does not long remain unoccupied. Seeds are soon scattered over it; the downy seeds of the thistles, wafted by the winds, are the first to take root, and after these comes the germs of various other plants, till at length the whole space is filled. If a rock be left entirely bare by the receding of water, the minute crustaceous Lichens in a few years eptirely cover it. These, dying, turn to earth, and the imbricated Lichens now have a bed to strike their roots into. These also die, and various species of Mosses succeed; and when, after some time, a sufficiency of mould has been formed, the larger plants, and even shrubs, take root and live.

The quickness of vegetation both in bot and cold climates is so astonishing, as to be perfectly unaccountable, were we not able to refer it to a most exalted wisdom.

The following is the Calendar of a Siberian or Lapland Year. Jane 23. Snow melts. July 17. Plants at full growth. Aug. 10. Plants shed their seod. July 1. Snow gone. 25. Plants in flower.

18. Snow. 9. Fields quite green. Aug. 2. Fruits ripe. From Aug. 18, to June 23, Snow and Ice. Thus it appears that only a month elapses from the time when the plants first emerge from the ground to the ripening of their seeds; and that Spring, Summer, and Autumn are crowded into the short space of forty-six days.

Again, in the torrid climates, where a scorching heat prevails through the greatest part of the year, we have a similar wonderful contrivance. In India, when the wet season commences, the rain falls in such abundance, that, in the course of a few hours, ponds of considerable depth are formed in every hollow place, in many of which there had not for several preceding months, been the least appearance of vegetation or even of moisture. No sooner, however, does the rain begin to fall, than vegetation commences; and, in less than twenty-four hours, the appearance of verdure can be distinctly perceived, whichever way the eye is directed. But the most surprising circumstance is, that very shortly after this verdure begins to appear, these newly-formed ponds are found swarming with fish of such size as to admit of being taken with nets, and to afford food for man. This circumstance is related by Dr. Anderson, on the authority of a very respectable person of Bombay, and was not stated until the fullest inquiries had been made, and the most satisfactory evidence had appeared respecting it.

Thus does the uniform voice of Nature exclaim aloud, that "the merciful and gracious Lord hath so done his marvellous works, that they ought to be had in remembrance.” The whole material system, throughout heaven and earth, presents a varied scene rich in use and beauty, in which nothing is lost, and in which the meanest and minutest creatures have their full designation and importance.—". Thus saith the Lord, thy Redeemer, and he that formed thee from the womb, I am the Lord, who maketh all things, who stretcheth forth the heavens alone, and spreadeth abroad the earth by myself.”

From the preceding observations, it appears that Natural History is capable of yielding to us innumerable subjects for both moral and religious study. Its chief tendency ought to be, to lead us, from the admiration of the works to the contemplation of their Author; to teach us to look, through Nature up to Nature's God. It is a study which terminates in the conviction, the knowledge, and the adoration of that gracious and merciful Being, to whose goodness alone we are indebted for every happiness that we enjoy.

These are thy glorious works, Parent of Good,
Almighty! Thine this universal frame;
Thus wondrous fair, thyself how wondrous then!
Unspeakable, who sitt'st above these heav'ns,
To us invisible, or dimly seen
In these thy lowest works; yet these declare
Thy goodness beyond thought, and power divina !

ON THE STRUCTURE AND FUNCTIONS

OF ANIMALS IN GENERAL.

MAMMIFEROUS ANIMALS.

(QUADRUPEDS AND WHALES.)

The class of animals denominated by Lipoæus, MAMMALIA, comprehends all those which nourish their offspring with milk supplied from their own bodies, and which have, flowing in their veins, a warm and red blood. It includes the whales, which from their external shape and habits of life, might be considered as fish. These inhabit exclusively the water, an element in which none of the quadrupeds can long sabsist; and they are furnished, like the fish, with fins; but, in every essential characteristic, they exhibit an alliance to the quadrupeds. Like the quadrupeds they have warm blood, produce their offspring alive, and nourish them with milk furnished from teats. In their internal structure they are, likewise, in a great measure, allied to the quadrupeds.

The bodies of nearly all the mammiferous animals are covered with hair, a soft and warm clothing, liable to little injury, and bestowed in quantity proportioned to the necessities of the animals, and the climates which they inhabit. In most of the aquatic quadruped's this covering, from its too free absorption of moisture, is wanting.

The head, in all the higher orders, is the seat of the principal organs of sense—the mouth, the nose, the eyes, and the ears. It is through the mouth, that they receive their nourishment. This contains the teeth, which, in most of the Mammalia, are used not only for the mastication of food, but as weapons of offence. They are inserted into two moveable bones called jaws. The front teeth, the office of which is to cut, are wedge-shaped, and so placed that, in action, their sharp edges are brought into contact, and thus divide the aliment. Next to the front teeth, on each side, are the canine teeth, or tusks. These are longer than the other teeth, conical and pointed; and their use is to tear the foo. d'The teeth at the back of the jaw, between which the food is masticated, are called grinders. In animals which live on vegetables, these are flattened at the top; but in carnivorous animals, their upper surfaces are furnished with sharp and conically-pointed protuberances. From the numbers, form, and disposition of the teeth, the various genera of quadrupeds have been arranged.

The nose is a cartilaginous body, pierced with two holes called nostrils. In some animals this is prominent, in others flat, compressed, turned upward, or bent down. ward. In beasts of prey it is often either longer than the lips, or of equal length with them. In a few animals it is elongated into a movable trunk or proboscis ; and in one tribe, the Rhinoceros, is armed with a born.

The eyes of quadrupeds are, for the most part, defended by movable eyelids, the outer margins of which are furnished with hairs, called eye-lashes. The opening of the pupil is in general circular ; but in some animals, as Cats and Hares, it is contracted into a perpendicular line'; and in Oxen, Horses, and a few others, it forms a tranverse bar. The opening contracts during the day, in order that the very sensi. ble retina may not be irritated by the rays of light; and, on the contrary, is expanded in the dark, io allow as many rays to pass as possible.

FUNCTIONS OF ANIMALS

17

The cars are openings generally accompanied by a cartilage which defends and covers them, called the external ears. In aquatic animals the latter are wanting, as, in them, the sounds are transmitted inerely through orifices in the head, which have the name of auditory holes. The most defenceless animals are very delicate in their sense of hearing, as are likewise most of the beasts of prey. In wild animals the ears are erect and somewhat funnel-shaped, capable of having their openings turned towards the quarter from which the sounds proceed; but in those that are tame and domestic, the ears are, for the most part, long and pendulous.

The head is joined to the body by the neck; and all those animals that often extend their arms or anterior feet forward, either to seize upon objects, as the Monkeys, or to fly, as the Bats, have, annexed to the upper part of the thorax, clavicles or collar-bones. The clavicle of the Mole is particularly remarkable, on account of its thickness, which exceeds its length. The collar-bones are wanting in such animals as use their anterior extremities for progressive motion only.

Most of the Mammiferous Animals walk on four feet. These are usually divided at the extremities into toes or fingers; but the extremities of some, as those of the Horse, end in a single corneous substance, called a hoof. The toes of a few of the quadrupeds terminate in broad flat nails, and of most of the others in pointed claws. Sometimes the toes are connected together by a membrane: this is the case in animals that reside much in the water. Sometimes, as in the Bat, the digitations of the anterior feet are greatly elongated, and have their intervening space filled by à membrane which extends round the hinder legs, and the tail, and by means of which they are enabled to rise into the air.

Man, and a certain number of animals, are capable of seizing objects, by surrounding and grasping them with their fingers. For this purpose the fingers are separate, free, flexible, and of considerable length. Man has such fingers on his hands only; but Apes and Lemurs have them both on their hands and feet.

With regard to the internal structure of Quadrupeds: that warm and red fluid which is calledblood, flows through the body, from the heart, its common reservoir, by a series of vessels called arteries, and returns by another series, denominated veins. During the circulation, various fluids are separated from the blood, and are carried through little vessels to be lodged in proper reservoirs. These fluids, which are termed secretions, are adapted to various purposes in the system.

The lungs of Mammiferous Animals consist of two lobes, and are placed within the thorax or chest. Into these the atmospheric air is inspired from the mouth ; and in them the vital air and the matter of heat are separated; the former, containing the only principle proper for the maintenance of life, and the latter being necessary towards keeping up the fluidity of the blood. The mephitic air, which remains after the separation, is expired. This act of drawing in the atmospheric air, separating the vital air and matter of heat, and ejecting the mephitic air, is termed respiration.

In digestion it is that the juices calculated to nourish and support the body become separated from the other less useful parts of the food. Reduced to a pulp, by means of the teeth and saliva, these pass through a canal which terminates in a large bag or reservoir, called the stomach. Here the aliment, penetrated and further dissolved by new juices, undergoes a trituration, or kind of grinding, from the action of the stomach; and the nutritive juices, which, on their union, are denominated chyle, are separated. These juices are taken up by little vessels called lacteals, and become converted into new blood and flesh. The alimentary canal again contracts on leaving the stomach, and, arranged in a great variety of folds, acquires the name of intestines. The residue of what is not converted into chyle traverses these numerous sinuosities, and at last is expelled the body.

The bodies of all Mammiferous Animals are supported by a frame of bones called a skeleton. To these bones are attached the muscles or flesh, assemblages of fibres held together by membranes, and terminating in a kind of cords, which are denominated tendons. The muscles, when excited, produce motion in the different parts of the body; and it is their action which gives to all animals the power of changing their place, and performing the various movements that are necessary to their wants.

The sensation of animals arises from an irritation taking place on the ends of certain chords called nerves. These are either prolonged from the spinal marrow, or they are united in pairs in the brain.

OF CETACEOUS ANIMALS, AS DISTINCT FROM QUADRUPEDS.

The Cetaceous animals constitute the seventh Order of Mammalia. They inhabit chiefly the seas of the Polar regions ; yet, like the quadrupeds, they breathe air by means of true lungs. They are consequently compelled to rise to the surface of the water to respire; and on this account it is that they always sleep on the surface. Their nostrils are open, and terminate on the summit of the head ; this peculiarity of structure enables them to draw in air without raising their mouth out of the water. The nostrils also serve them as canals for expelling the superfluous water which they take in at the mouth every time they attempt to swallow their prey: They have also warm, red blood; and they produce and suckle their offspring in the same manper as the quadrupeds. They likewise resemble them in having movable eye-lids and true bones; and in their power of uttering loud and bellowing sounds, a l'aculty altogether denied to the scaly tribes.

The Cetaceous animals have a smooth skin, not covered with hair. Their feet are very short; those on the fore-part of the body being formed like fins, and the hinder. ones being united into an horizontal tail.

The fat of these animals is what we term blubber. It does not coagulate in our atmosphere, and is probably the most fluid of all animal fats. It is found principally on the outside of the muscles, immediately under the skin, and is in considerable quantity. The blubber appears principally to be of use in poising their bodies : it also prevents the immediate contact of the water with the flesh, the continued cold of which might chill the blood; and, in this respect, it serves a purpose similar to that of clothing to the human race.

It is probable that the Cete swallow all their food whole, for they are not furnished with irrstruments capable either of dividing or masticating it. In place of teeth, the mouths of some of the whales are supplied with lamina of horn called whalebone.

This substance is attached to the interior part of the upper jaw, is extremely elastic, and consists of thin plates of cousiderable length and breadth, placed in several rows, encompassing the outer skirts of the upper jaw, like teeth in other animals. The lamicæ are parallel to each other, having one edge towards the circumference of the mouth, and the other towards the interior. The outer row is composed of the longest plates, some being fourteen or fifteen feet in length, and twelve or fifteen inches broad: but towards the anterior and posterior parts of the mouth they gradually become very short.-The whalebone is supposed to be principally of use in the retention of food till swallowed : for, as the fish, and other marine animals, which the whales catch, are very minute when compared with the size of their mouth, a quantity sufficient for their nutriment, without some such guard as this, could scarcely be retained.

From these animals being resident entirely in the water, and generally far removed from the haunts of man, we cannot be supposed to have acquired any very correct knowledge of their manners or habits of life : even their species are but imperfectly knowp.

The Mammiferous Animals have been divided by Linnæus into seven orders.

1. Primates, which have four front teeth in each jaw; and one canine tooth on each side in both jaws. The principal animals of this order are the Apes, Lemurs, and Bats.

2. Bruta. These are entirely destitute of front teeth. The tribe consists of the Sloths, Ant-eaters. Rhinoceros, Elephant, and Manati.

3. · Ferce. The Feræ have genually six front teeth in each jaw; and one caninetooth on each side, in both jaws. They consist of Seals, Dogs, Cats, Weasels, Otters, Bears, Kangaroos, Moles, Shrews, and Urchins.

4. Glires. The animals denominated Glires have two long front-teeth in each jaw; and no canine-teeth. They consist of the Porcupines, Caries, Beavers, Rats, Marmots, Squirrels, Dormice, Jerboas, Hares, and Hyraxes.

5. Pecora. The Pecora are destitute of front-teeth in the upper-jaw, and on their feet have cloven hoofs. All the species ruminate or chew their cud. The tribes are the Camel, Musk, Deer, Giraffe, Antelope, Goat, Sheep, and Ox.

6. Belluc. These have obtuse front teeth in each jaw, and unilivided hoofs op their feet; and consist of the Horses, Hippopotamus l'apir, and Hogs.

7. Ce e or Wales. Instead of feet, the Cete, which comprise the Närwal, Whale, Cachalot, and Dolphin tribes, have fins. On the front and upper part of the skul there are spiracles or breathing holes. The teeth differ in the different species and the tail is flattened horizontally. They are inhabitants only of the sca

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