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number, and general character of the teeth, they combined the peculiarities of the tapir and rhinoceros. Unlike the tapir they had, however, only three toes on each foot. Their legs also were longer, and their

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general form more slender than that animal, at least in the species of medium size; and in this respect the Palæotherium was probably intermediate between the tapir and the horse.

The Anoplotherium* may be considered as a still farther departure from the tapir towards the ruminants, having been far less clumsy and more agile in its movements than either the Palæotherium or the tapir. The animals of this interesting group exhibit two peculiarities which are observed in no other quadruped, the feet having only two toes, and the

Ava (ana), privative; onλos (oplos), a weapon; Onpiov (therion), a beast an animal without defensive or offensive weapons, (having no tusks.)

teeth being placed in a continuous series without any interval between the incisors and the molars, as is the case with all other Mammalia except man. For this reason, namely, the absence of tusks, or canine teeth longer than the other incisors, the animal has received its name of Anoplotherium, or "weaponless;" and there are three well-marked sub-genera, all of which appear to have been abundantly present during the older tertiary period. They none of them had a proboscis or produced snout; and in this and other respects they rather resemble the ruminants than the pachyderms; but one species seems to have been well adapted to live in swamps and marshes, and probably for that reason its remains are more common than those of the other forms.

This first species belongs to a division considered typical, and attained the largest dimensions. It was about as tall as a dwarf ass; but its body was longer in proportion, and its tail of enormous size, giving the animal the general aspect of the otter. It is most likely that this species lived chiefly near the water, feeding on roots and the succulent leaves of aquatic plants. Its total length, including the tail, would be nearly eight feet; its skin was probably either naked or covered with smooth hair like the otter; its ears were no doubt short, and its whole appearance must have been that of an animal fitted to inhabit and seek its food in water. By far the most remarkable peculiarity in this species is the tail, which was composed of nearly thirty vertebræ, and equalled, if it did not surpass, the length of its body. Cuvier has observed that no living animal, with the exception of the kangaroo, has so long and so powerful a tail.

The species characteristic of the second group of Anoplotheres, called Xiphodon (see fig. 124), was very different, both in its proportions, its size, and its habits, from the more common species just described. It is called gracile, or slender, as an indication of its superior agility and slender proportions; and, indeed, the graceful elegance of the bones of its skeleton reminds one more of the structure of the gazelle than of any other quadruped. Its height was

about as large as that of a goat, but its head and trunk would indicate a much smaller animal, as the bones

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of the extremities were excessively elongated, and in striking contrast to the species first described. Light

and elegant as the gazelle, it would course rapidly along on the banks of the lakes and rivers, or on the borders of those marshes in which the former species lived, and would feed on the aromatic herbs, and browse on the young shoots and tender buds of shrubs growing in such localities. Its movements would be free and unencumbered; and, like most of the more active Herbivora, it was doubtless a timid animal, and provided with large and very mobile ears, readily turned in any direction at the slightest approach of danger. There can be little doubt, too, that it was covered by very short hair, and that in all external characters it resembled closely the ruminants (such as the smaller deer), and could hardly have been distinguished from them.

The third group of Anoplotheres contains several species much smaller than either of those just described, one of which resembled the hare, not only in dimensions but also in the proportions of its limbs, which are so contrived as to have given it great swiftness of motion, and therefore a means of escape from its enemies. If the Xiphodon was the roe of the antediluvian world, and, from the almost total absence of true ruminants, it is not impossible that the place of the deer tribe was occupied by the pachyderms, this little species represented in the same way the smaller rodents, such as the hare and the rabbit.

It is interesting and curious to find that there is another small pachyderm, whose remains have been found in the London clay, but which belongs to a distinct genus, still more closely resembling the hare, and was even provided with the large full

eye so strikingly characteristic of that timid quadruped. This genus approaches also very closely to another from the Paris Basin, and both of them resemble a small quadruped called hyrax, a native of Africa and some parts of Asia, more than any other existing pachyderm.

Having now considered in detail these various groups, let us next attempt to group together the principal geological observations of the early tertiary period in Europe. In doing so it may be noticed, first, that at this time all the great plains of Europe and the districts through which the principal rivers now run were then probably submerged; and that in all probability the land chiefly extended in an east and west direction, far out in the Atlantic, possibly even trending greatly to the south and connecting the western shores of England with the western islands of Africa. The land now forming the great mountain chains intersecting Europe, the Pyrenees, the Alps, the Appenines, the mountains of Greece, the mountains of Bohemia, and the Carpathians, existed then only as chains of islands in an open sea. Elevatory movements, having an east and west direction, had already commenced, and were producing important results, laying bare the Wealden district in the south-east of England. The southern and central European district, and parts of western Asia, were then the recipients of calcareous deposits (chiefly of Foraminifera), forming in deep water what is now the Appenine limestone, while the numerous islands were gradually lifted above the sea level, and fragments of disturbed and fractured rock were washed upon the neigh

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