Between the occipital, the parietal, and the sphenoid, are inserted the temporal bones, which, to a certain extent, belong to the face.

In the fœtus the occiput is divided into four parts, the body of the sphenoid into two, and three of its pairs of alæ are separate; the temporal bone into three, of which one serves to complete the cranium, another to enclose the labyrinth of the ear, the third to form the walls of its cavity, &c. These portions of the cranium unite more or less quickly, according to the species, and end by perfect union in the adult.

The face is formed by the two maxillary bones, between which the nasal canal passes. Before these, are two intermaxillary, behind two palate bones, and between them descends the single plate of the ethmoid bone, named the vomer. At the entrance of the nasal canal are the bones which form the nose. The molar or cheek bone of each side, unites the maxillary to the temporal, and often to the frontal bone; and finally, the lachrymal cavity occupies the internal angle of the orbit, and sometimes part of the cheek.

The tongue, in the Mammalia, is always fleshy, and attached to the hyoid bone, which bone is suspended by ligaments to the cranium.

Their lungs, two in number, are composed of a mass of small cells, inclosed without adhesion in a cavity formed by the sides of the diaphragm, and lined by the pleura. Their organ of voice is at the upper extremity of the trachea or windpipe; and a fleshy continuation, named velum palati, establishes a direct communication between their larynx and the back part of their nostrils.

Living on the earth's surface, as do the greater part of the Mammalia, they are exposed to alternations of heat and cold, and their bodies have, in consequence, a covering of hair, which is thicker in the colder, and more scanty in the warmer regions. The Cetacea, which inhabit the sea, are, however, totally destitute of this covering.

The intestinal canal of the mammiferous animals, is suspended by a fold of the peritoneum, called the mesentery, which contains numerous conglobate glands for the lacteal vessels. Another production of the peritonæum, named the epiploon, hangs before and beneath the intestines.

The generation of the Mammalia is essentially viviparous. The fœtus, after conception, descends into the uterus, to the inner surface of which it is attached by means of an arrangement of vessels, termed the placenta, through the medium of which, nourishment is derived. The young, for some time after birth, are nourished by a particular secretion of the mother, (milk,) produced in the mammiferous animals, after parturition, and drawn by the young from mamme, or teats. It is from this last character that the term Mammalia has been applied to this class a character exclusively proper to them, and by which they are more easily recognized than by any other external distinction. The essential characters of the Mammalia are taken from the organs of touch, and the organs of mastication. On the first, depend the power and dexterity of the animal; and from the second,

may be deduced the nature of its food, and the consequent structure of its digestive apparatus. On these characters are founded the division of mammiferous animals, into orders.

The degree of perfection of the organs of touch, may be estimated according to the number and mobility of the fingers, and according to the greater or less depth with which their extremities are covered by the nail or hoof. A hoof, for instance, which envelopes that part of the extremity which would otherwise touch the ground, blunts the feeling, and renders the foot incapable of seizing. The opposite extreme is, when only a single lamina covers the upper surface of the end of the finger or toe, leaving to the other all its sensibility. The nature of the food may be judged of by the appearance of the molar teeth, to the form of which the articulation of the jaws always corresponds. For cutting flesh, the teeth require to be edged like a saw, and the jaws to close vertically, like scissors. To bruise grains or roots, it is requisite that the molars have a flat crown; that the jaws should move horizontally, as well as vertically; and that the teeth should be composed of parts of unequal hardness, to give them the necessary inequalities for this operation. The hoofed animals are all necessarily herbivorous, and possess teeth of this description, since the structure of their feet precludes them from seizing living prey.

Animals with unguiculated toes or fingers, on the contrary, are susceptible of more variety in their modes of subsistence; for, besides the form of the molar teeth, they differ materially among themselves in the mobility and delicacy of their toes or fingers. There is one characteristic, however, which exercises a mighty influence on the dexterity of the animals possessed of it, and which multiplies or greatly varies their modes of action. This is the faculty of opposing a thumb to the other fingers, and of thus being enabled to seize with facility the most minute objects. This opposition of a fifth member to the other four, constitutes what is properly called the hand, an organ which is carried to the highest degree of perfection in man, in whom alone the anterior extremities are free.

These various combinations strictly determine the nature of the different mammiferous animals, and afford the characteristics from which orders are formed. In the following pages, the Mammalia will be arranged under the following orders:

The total number of mammiferous animals described, according to Desmarest, is about eight hundred and fifty, including, however, many species imperfectly ascertained, and the fossil Mammalia; of which, belonging to the order Quadrumana, are one hundred forty-one,-Cheiroptera, ninety

seven,- Feræ, one hundred seventy-six,-Marsupialia, forty-seven,Glires, one hundred forty-nine,-Edentata, twenty-four,-Pachyderma, fifty-five,-Ruminantia, ninety-seven, -Cetacea, sixty-two. Of these about three hundred and thirty are frugivorous, or herbivorous; eighty omnivorous; one hundred and fifty, insectivorous, and two hundred and forty, carnivorous, in a greater or lesser degree. The number of terrestrial species domesticated by man, (but perhaps including all that are really useful,) amount only to thirteen.

MAN stands alone in the order and genus to which Naturalists have referred his species. Differing widely in physical conformation from all

1 The order Bimana embraces animals with teeth of three kinds; the posterior extremities proper for walking; the anterior furnished with hands; nails flat; body vertical; two pectoral mamma; stomach simple; orbital and temporal fossæ distinct.

Homo sapiens. The genus Homo has four upper and four lower incisor teeth; two upper and two lower canines, one on each side; molars, five above and five below, on each side. The whole number of his teeth, thirty-two.

other classes of animated beings, and distinguished by reason and the power of speech, this wonderfully constructed being seems the bond of connection between the material and immaterial worlds. Possessed of mental powers which raise him beyond the level of the surrounding creation, and connect him with higher orders of existences, man is the only being who looks forward to futurity, and intuitively perceives his connection with and dependence upon the great Source of Intelligence. While the inferior animals enjoy unalloyed the blessings of life and present enjoyment, man combines the past, the present, and the future in his calculations of happiness; and while some parts of his organization connect him with creatures around him, and sober his rule over beings with animal feelings of pleasure and pain as acute as his own, his intellectual powers, unfettered by the material organs which are their instruments, trace the Divinity in all the parts of creation. Hence has arisen the religious feeling among every tribe of human beings, however rude; and man alone, seems to connect himself with the Great Author of his being, through the medium of intellectual homage and worship, according to his conceptions of that Almighty Being, the Creator and Preserver of all.

While reason places man at such an infinite distance from the inferior animals, the faculty of articulate speech, and an artificial language, widen the barrier still further; for although some of the animals possess the power of articulation in a considerable degree, and can communicate by natural signs, significant to those of their own species, they totally fail in those powers which enable man to classify objects, and to employ sounds or signs as an instrument of thought. Brutes possess, indeed, the powers of sensation, perception, and memory, and seem to be capable of intellectual operations to a certain extent; but their action is extremely limited, and bounded to the supply of their bodily wants; and, though susceptible of a species of education, their imitative powers are neither subservient to the improvement of the individual nor his species.

The faculty which seems to direct the inferior animals, in most of their operations, essentially different from any thing like human intelligence, is called instinct. This wonderful faculty, surer in its limited aims than reason, bears, however, no proportion to the general intelligence of the animals which exercise it; for it has been remarked, that those in whom the instinctive propensity displays the greatest seeming wisdom and contrivance, upon some occasions, are upon others, remarkably deficient in sagacity.

The physical structure of man, also, widely separates him from the other portions of the mammiferous class. But these variations, in form and proportion, are neither so prominent, nor so totally different in character, from the other animal structures, as to account for the superiority which he enjoys, Destined to be nourished on substances used in common with other animals, the mechanism of his frame must so far correspond with theirs, as to be

able, like them, to convert these substances to the fluids which support his animal life; and his organs of sensation must necessarily be analogous, in some degree, to those of beings on whom the material world is destined to make similar impressions. But no material organs which man possesses, abstracted from the mind of which they are but the instruments, can account for this intellectual supremacy; and those hypotheses which would trace man's intellectual and moral powers to the absolute or relative size of the brain or other material organs, have miserably failed in connecting mind with matter, or thought with organic structure.

The structure of the human frame, however, is wonderfully adapted to the various purposes for which it is destined; and even physically considered, seems the worthy habitation of a being placed at the head, and with the control of animated nature. Man, indeed, considered as an animal, is the only one which walks erect in a vertical position; the only one with hands at the anterior extremity, distinct from the organs of locomotion, and free for executing his purposes. Contrary to what is found in any other mammiferous animal, the structure of his body demonstrates that man is destined to walk erect.

The foot is entirely different from the posterior hand of apes, and furnishes a larger and firmer base than that of any other animal. It would be impossible for man, even if he desired it, to walk on the four extremities, his feet being almost inflexible, and the great length of his thigh would bring his knee to the ground. His shoulders, also, being too much separated, and his arms too far extended from the central line, would produce a very ineffectual support for the upper part of the body. The arteries which supply the human brain, not being subdivided, as in most quadrupeds, the blood necessary for an organ of such volume, would be poured in too copiously and rapidly, if he should assume the horizontal position.

According to Cuvier, no quadruped is comparable to man, for the magnitude of the hemispheres of the brain in proportion to the size of the face. Though the external senses of man are less energetic than in some other animals, they are, however, extremely delicate. His eyes are directed forwards, and thus, though he does not see to both sides of him at once, like most quadrupeds, there is a greater unity in the result of the visual operation. Of all animals, he can best distinguish the various degrees of sound, and he appears to be the only creature whose sense of smell is sufficiently delicate to be affected by unpleasant odors.

Fruits, roots, and succulent vegetables, appear to be the natural food of man. His hands afford him facility in procuring these, and his short and comparatively weak jaws, his canine teeth, scarcely projecting beyond the line of the others, and his tuberculous molar teeth, are little calculated to feed on herbage, or devour flesh, unless those aliments are previously prepared by fire. The organs of digestion in man, are in conformity with