cond, such as inhabit the earth. The terrestrial, may be again divided into aquatic and terrene, since not the earth only, but its waters are inhabited by various tribes, familiarly known under the titles of fresh water fish, shells, &c. As organic bodies, fossil remains are also divided in animals and vegetables. The former including all such as had animal life, as quadrupeds, fish and shells; the latter, plants of every kind found in the fossil state.

Indications of Violent Changes. That the earth on which we live has suffered violent and extensive changes, is almost every where indicated by its external appearance; and when we come to examine the interior of its crust, this idea is confirmed, in the most positive manner, by the obvious fact that its rocks have been fractured, and its strata dislocated. At what period or periods, these mighty changes took place, we have no means of knowing; but that its surface has been materially altered since the formation of the more recent rocks, and subsequently to the creation of organized beings, is clearly proved by their remains now preserved in its strata.

In some instances, very extraordinary collections of bones, remains of fish, vegetables and other organic bodies, have been found in situations, and under circumstances, which, though indicative of violent revolutions, place all suppositions with respect to their origin at defiance.

Thus, in the valley of the Thames, in England, at a certain locality, in Essex, there is an alluvial deposite, resting on chalk. "This," says Mr. Brande, "contains such a remarkable assemblage of organic remains, some of vegetable, and others of animal origin, as almost to baffle all conjecture as to whence they came, and under what circumstances they were brought together. The remains of sea animals are blended with those of the land, quadrupeds with fish, and fresh water fish with those peculiar to the ocean. Animals of the land, the air, and the water, are assembled together in most unaccountable incongruity; fruits and leaves, hazel nuts and pine cones, are mixed with shark's teeth, crab's claws, and oyster shells."

In the island of Sheppy, there exists a similar assemblage of various species of shells, mixed with fossil fruits. Of the latter, 500 varieties have been found. At Brent

ford, phenomena of the same kind, and not less extraordinary, have been discovered. Here exists a collection of sea shells, shark's teeth, bones of the elephant, hippopotamus, ox and deer, together with fresh water shells; "the whole," says Mr. Brande, "calculated to impress us with the idea of the destruction of a vast menagerie, in which animals of all denominations, and from all quarters of the world had been associated."

FOSSIL QUADRUPEDS.

In their descriptions of fossil remains, authors have more generally commenced with those belonging to the lowest strata, or those, which in the order of time, as shown by the strata, were first called into existence, such as extinct species of plants, shells, &c. But as these are not easily understood, and as there is no advantage to the learner in such an arrangement, we have thought proper to commence with the more perfect animals.

The number of quadrupeds, the classes and orders of which, have been determined by Cuvier, solely by an examination of their bones, amount to 150. Of these, ninety species were before entirely unknown to naturalists, and are, therefore, supposed not to inhabit the earth at the present time, their entire races having perished at the period when their bones, found in the most recent strata, were there buried. Ten or twelve of the others so nearly resemble known species, that no doubt remains of their identity. Many of those which remain, present kindred features with known species, but the comparisons have not been made with sufficient care to remove all doubt, and, therefore, it is still uncertain whether their species exist or not.

Of the ninety unknown species, about thirty belong to genera still living, and the remaining sixty to genera entirely new.

With respect to the classes and orders to which these animals belonged, about one fourth of the 150 species were oviparous (egg laying) quadrupeds, as the alligator, lizard, and tortoise. The remaining were mammiferous, or milk-giving animals, as the elephant and mastodon. Of the latter, more than one half were non-ruminant, hoofed quadrupeds, as the horse and tapir.

From these facts thus developed, concerning the animals of the primitive, or ante-diluvian world, it might perhaps be supposed that some theory could be formed with respect to the proportions of the different genera, which then inhabited the earth, and by a comparison of these, with the genera now existing, we should be enabled to see the difference. But it would be premature to form any hypothesis on this subject at present, since we know not but there are hundreds of extinct species still undiscovered.

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Cuvier has proved, as we shall see directly, that the extinct species of quadrupeds, are not varieties of those now in existence, but that there exist distinct specific differences between them. A species," says he, " comprises all the individuals which descend from one another or from common parents, and those which resemble each other, as much as they resemble themselves." Hence the varieties of a species, are the result merely of such changes as take place in the color, size, and fineness of the fur of animals, and which may be caused by a difference of climate, of food, or,the domestication of the species; these varieties may therefore produce the exact likenesses of their parents. For example, the dog is a genus; the pointer is one species, and the greyhound is another. Now every one who is conversant with dogs, knows that pointers may differ from each other in color, size, and shape, and even from the same parents it is seldom that two precisely similar can be found. These are varieties of the pointer, but the species are not changed, for their instincts, habits and general appearance, are the same with those of their parents. The same variations may be observed in the greyhound, and indeed all other species of dogs. But if the races are kept distinct, there are no circumstances of climate, or keeping, that will change the greyhound into the pointer, or the pointer into the greyhound. The species are therefore entirely distinct and unchangeable.

"The fox and the wolf," says Cuvier, "inhabit every country from the icy to the torrid zone; they experience in this immense interval every change of climate, and condition, and yet the species have suffered no other change than a slight variation in the beauty of their fur. The same accurate observer compared the skulls of foxes from the north of Europe and from Egypt, with those of

France, but found no appreciable differences. Hence we learn that the species of animals are not changed by time and circumstances, as some have thought to be the case."

Before pro

Means of distinguishing Fossil Bones. ceeding to individual fossil species, it is necessary to describe the method by which naturalists have been enabled, by examining their petrified bones, to distinguish these unknown animals from each other, and from those now living. This art, or science, originated with the acute and laborious Baron Cuvier, and by him was brought to a degree of perfection, to which little has been added by others.

The principle on which this discrimination is founded, is the peculiar, and perfect organization of each species, so that one part is invariably, and exactly adapted to another, and is indicated by it. Each animal constitutes a whole, one systematic cycle, whose parts are in mutual correspondence, and concur to the same definite action, by a reciprocal re-action. None of these parts can change without a symmetrical change in the others; and hence each taken by itself, indicates and gives form to all the

rest.

Thus if the organs of an animal are so constituted as to digest only raw flesh, its jaws must be constructed for devouring its prey; its claws for seizing and tearing it; its teeth for cutting and dividing it; the entire system of its organs of motion for pursuing and overtaking it; its organs of sense for descrying it at a distance; and even its brain must be qualified for exercising the instinct of self concealment, and the art to ensnare its victim. Such is the general condition of the carnivorous temperament; every animal endowed with which, must combine them all, for otherwise its race could not subsist.

For the jaw to seize its prey there must be a certain kind of articulation, which gives prominence to the cheeks, and fits the bones to receive the insertion of strong muscles, for without these any such articulation would be useless. To enable the animal to carry off its prey, there must be a certain degree of strength in the muscles of the neck, and hence results a determinate form in the vertebræ, and the hind part of the head, to which these muscles are attached.

Whoever will compare the bones of a cat with those of a rabbit, will see how these parts differ, and if he will study the subject, he will soon convince himself, why the bones of the rabbit, independently of the teeth, could not have been fitted for the purposes of a rapacious animal.

That the claws may seize the prey, there must be a certain mobility in the talons, and a certain degree of strength in the toe joints, and thence there must result a corresponding distribution of muscles, and tendons, so that lightness and power may be combined. The shoulder bones in such animals must have great firmness, otherwise the legs will not be fitted for the uses of the claws, and this firmness of bone is thus prepared to receive the insertion of strong muscles, by which the required power is given.

It is unnecessary to show how the other parts of a prowling animal are adapted to each other, so that the whole machinery of bones, muscles, joints and tendons, all combine to the accomplishment of the same end. The parts of any animal, are indeed a "collection of wonders," and he who does not behold in them the traces of Infinite Wisdom and design, must want either understanding or sight.

"In a word," says Cuvier, "the formation of the tooth indicates the structure of the jaw, and its kind of articulation; the structure of the shoulder bone, shows the form of the feet, just as the equation of a curve, involves all its properties; and as by assuming each property separately as the base of a particular equation, we should re-produce both the ordinary equation, and all its properties; so the nails and shoulder blade indicate the articulation of the jaw; the thigh bone, and the other bones, taken separately, give the form of the tooth, or are given by it in their turn.

Since the mechanism of every animal involves certain fixed and invariable principles and proportions which belong to the whole race, by ascertaining what these are, we can readily distinguish one tribe, or species from another, though the differences may be ever so slight. To the most common observer, the entire skeleton of a horse would be distinguished from that of an ox, by the size and proportions of the whole; and by comparing the thigh bones of the two animals, he would readily distinguish