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division. We can trace several of our existing quadrupeds, such as the badger, the hare, the fox, the reindeer, and the wild cat up to the earlier times of the Pleistocene, and not a few of our existing shells, such as the great pecten, the edible oyster, &c., up to the greatly earlier times of the coralline crag. But at certain definite lines in the deposits of the past, representative of certain points in the course of time, the existing mammals and molluscs cease to appear, and we find their places occupied by other mammals and molluscs; even such of our British shells as seem to have enjoyed as species the longest term of life cannot be traced beyond the times of the Pleiocene deposits. We thus know that in certain periods, nearer or more remote, all our existing mollusca began to exist, and that they had no existence during the previous periods, which were, however, richer in animals of the same great molluscan group than the present time-a great number of still older shells have been detected in a single deposit of the Paris Basin, the Calcaire grossier, and a good many more in a more ancient formation still, the London clay. On entering the chalk, we find a yet older group of shells, wholly unlike any of the preceding ones, and in the Oolite and Lias yet other and different groups,' &c.

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Thus testimonies to the same effect might be multiplied from almost every respectable book on geology. All writers agree on the subject that certain genera or species have made their appearance for the first time in certain deposits; and as this is fatal to the Theory, we need not be surprised to hear Mr Darwin stoutly declaring that this evidence is false; this is his own word, 'why do whole groups of allied species appear, though certainly they often falsely appear, to come in suddenly on the several geological

stages? (497). So their sudden appearance is acknowledged, only we are to understand that they had also existed in antecedent formations, though they cannot be found. Before, however, we hear the explanation offered to us of these sudden appearances, we must yet more closely press the evidence before us.

We clearly understand then that the last great formation of the Tertiary, with its classification of ages in chronological succession, introduces us to the fauna and flora that now exist; for though there is a manifest difference, if we compare the organic beings of the lower divisions with those of the Pleistocene, and of the present era, called sometimes the post-Tertiary, yet there is still a similitude and a connection, and everything seems in this formation, taken as a whole, to be preparing for the present state of things, and the introduction of the actual inhabitants of the earth. When we reflect,' says Lyell, 'on the tranquil state of the earth, implied by some of the lacustine and marine deposits of this age, and consider the fulness of all the different classes of the animal kingdom, as deduced from the study of the fossil remains, we are naturally led to conclude, that the earth at that period was in a perfectly settled state, and already fitted for the habitation of man' (iv. 129).

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The Tertiary formation is separated from the preceding chalk formation with such marked difference, the character of the two eras is so wide apart, the biological chasm is so vast between them, that palæontologists speak of them as if they were distinct worlds. The Tertiary is, as it were, severed and walled off from the next formation beneath it, and by this strong separation the argument too is hemmed in and confined to a comparatively small compass.

M. Deshayes first pointed out that which Lyell fully confirms that no species of fossil shell has yet been found common to the Secondary and Tertiary formations. This marked discordance in the organic remains of the two series is not confined to the testacea, but extends, as far as careful comparison has yet been instituted, to all other departments of the animal kingdom, and to the plants. I am informed by M. Agassiz that after examining about 500 species of that class, in formations of all ages, he could discover no one common to the Secondary and Tertiary rocks-nay, all the Secondary species hitherto known to him, belong to the genera distinct from those established for the classification of the Tertiary and recent fishes. There appears to be a greater chasm between the remains of the Eocene and Maestrecht beds (Secondary) than between the Eocene and recent strata; for there are some living shells in the Eocene formations, whilst there are no Eocene fossils in the newest Secondary group' (iv. 217).

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Similar are the statements of Professor Ansted.

'At the close of the Secondary period (that is, the commencement of the Tertiary) all these older forms appear to have been completely destroyed, the newer forms becoming much more abundant and widely distributed, and not one species remaining identical with anything that exists in the Secondary rocks' (ii. 71).

By all this then we see that the Eocene formation of the Tertiary begins the grand drama of the existing state of things. The curtain of creation rises, and Nature is seen earnestly occupied in her grand laboratory, introducing in well-considered pauses the animated scale which is to terminate in man. We find in the Eocene, carnivorous land-animals unknown before, and by their pre

sence alone assuring us of the existence of other animals. destined to be their prey. In the Meiocene there has been discovered a peculiarly destructive feline quadruped, with the upper canines much elongated, trenchant, sharppointed-sabre-edged, whence the name Machirodus has been proposed for this feline sub-genus. It was represented by species as large as a lion, and by others of the size of a leopard. Then later on there was a large Pleistocene lion, found in England and Belgium; and the gigantic bear, wolves, foxes, wolverines, marten cats, hyænas, &c. The herbivorous class prospered, the redundancy of their increase required repression, and hence this large provision of their enemies.

Then we come to the celebrated animals of the Paris Basin, the palæotherium, amplotherium, dinotherium, &c., and the fossils of the Tertiary of Northern India, a prodigious display of a by-gone age: new and singular forms of the Carnivora, Felidæ, and Canidæ; colossal bears, and genus allied to the otter, but large as panthers; two species of mastodons, two new species of elephants, new species of rhinoceros,† hippopotamus, new species of

* Owen, p. 418.

Of the fossil species, that which was the earliest known, and which is the most frequently met with in the middle and northern parts of Europe, as well as in Asia, is distinguished from the living species by a very remarkable circumstance. What particularly attracts our attention in the rhinoceros is the situation of the bulky horn which it carries; and when we examine its skeleton to examine what base has been furnished by nature, to sustain so weighty an organ, we perceive with surprise that it is placed upon the extremity of the bones of the nose, which form a very thick arch it is true, but without any support from the rest of the skull. The species which seems to have been the most common in the ancient world, would appear to have been, in this respect, much more advantageously organized than the existing species. It was, in fact, provided with a kind of bony partition in the nostrils, which, serving as a prop to the arch that supported the horn, gave greater solidity to it. Add to this favourable circumstance that the arch formed by the bones of the nose is, in the fossil species,

the horse, of the camelopard, and then, in all countries, the Elephas primigenius, in prodigious herds: Nature in that era rejoicing in her gigantic productions, and in creatures of colossal frame.

Such at a glance was the scene of those days; the giant quadrupeds have for the most part disappeared, but the branches of their families, in smaller or altered form, are recognized amongst living creatures. But now the question comes, whence spring those huge pachydermata? we find the great creatures in the Tertiary, there were giants in those days,' but we do not find any trace of them in the antecedent formations. We have already seen that there is a broad gulf between the Tertiary and Secondary, that life was altogether different, if we compare the two eras; but here in the Tertiary a prodigious aggregate of unusually large animals crowds upon us, they march into the scene in solemn grandeur from some unknown birth-place, and who shall tell us of their birth and the secret of their first appearance?

What is Natural Selection to do here? She has not time enough to produce a tooth of one of these creatures, and as for a proboscis she would require some myriads of

less elevated, and more depressed towards the lower jaw. The immense majority of fossil bones belong to this species, which, until within these few years, was the only one known.'-Bertrand's Revolution of the Globe, page 155.

In this statement we see that the ancient rhinoceros was much more advantageously organized than the existing species; that a 'favourable circumstance' appeared in its organization, the very phrases used by Mr Darwin, passim. Now, according to his Theory, Natural Selection ought to have made these advantageous and favourable organizations a means of advancing the favoured species above all its competitors. All other unimproved creatures of its kindred ought to have been infallibly exterminated;' but it so turns out that the rhinoceros with the advantageous organization has perished, and the rhinoceros with the inferior organization is triumphant.

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