The Elephants, two or three species of which constitute in the modern world the sole representatives of an order, are a remnant of an ancient race once vastly more numerous. They appear in Europe and Asia in the Miocene, when they were represented by three distinct genera (_Elephas_, _Mastodon_, and _Dinotherium_). The second genus (Fig. 181) differs from the proper Elephants in having tuberculated teeth, indicating a more swinish habit, and probably a more fierce disposition. The third (Fig. 182) is remarkable for the immense size of some of its species, far exceeding the modern Elephants, and has the farther peculiarity of a pair of descending tusks on the lower jaw, constituting a strong and heavy grubbing-hoe, with which it could probably dig deeply for roots. So important was the group in Miocene times that seven elephants are already known from this formation in India alone, besides three species of Mastodon. Four or five Miocene Mastodons are known in Europe, besides two _Dinotheria_; and the true Elephants appear there in the Pliocene, and continue to the beginning of the Modern. The elephantine animals are not known in America till the Pliocene, but in that and the Pleistocene, and perhaps up to the human period, the western continent, now altogether destitute of elephants, possessed several species both of _Elephas_ and _Mastodon_, which extended, as in Siberia, even into the Arctic regions; and, as we know from specimens preserved in a frozen state in the latter region, some of the species were so protected by dense fur as to be able to endure extreme cold. The candid Gaudry closes his summary of the history and affinities of the elephantine animals with the words: “However, the sum of the differences compared with that of the resemblances is too great to permit us to indicate any relation of descent between the proboscidians and the animals of other orders known to us at present.” So these greatest of all the animals of the land, with their strangely specialised forms and almost human sagacity, stand alone, without father or mother, without descent. [Illustration: FIG. 181.—_Mastodon ohioticus._ An American Elephant. Post-Glacial.] [Illustration: FIG. 182.—Head of _Dinotherium giganteum_. Greatly reduced. Miocene of Europe.] [Illustration: FIG. 183.—Wing of _Vespertilio aquensis_. An Eocene Bat. After Gaudry.]