Page:Popular Science Monthly Volume 21.djvu/511

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particulars, while some authorities have been even found to suggest that it represents a connecting link between the elephants and the sea-cow or manatee order (Sirenia). The tusks of dinotherium spring from the lower jaw (Fig. 4); and instead of being curved forward and upward, they bend abruptly downward and backward. The use of these tusks is extremely difficult to determine, but it has been suggested that the dinotherium was an aquatic animal, living in shallow waters, and that these huge teeth may have enabled it to root up the plants on which it fed, or have enabled it to climb, as does the living walrus, from the sea on to the river-banks.

PSM V21 D511 Restoration of dinotherium.jpg
Fig. 4.—Restoration of Dinotherium.

In addition to these latter elephants, which are essentially distinct from the living species, certain extinct forms may be mentioned which, in their essential characteristics, resembled existing proboscidians more or less closely. Thus, we know that elephants closely related to the Indian species existed in Asia in Miocene times, the remains of at least six species being obtained from Indian deposits of that age; and we also know that Europe boasted of elephants in that period of geology known as the "Pliocene"; for in the deposits of France and Italy, as well as in the formations of that age in Britain, elephant remains occur. Later in point of time come the curious "pygmy elephants" of Malta, whose remains exist in that island, and whereof one (Elephas Melitensis) attained the size of a donkey, while another [Elephas Falconeri) was smaller still, and averaged two and a half or three feet in height.

The geological order and the succession in time of these various elephants is important to trace; for the unraveling of so much of the past history of the elephants as is known to us depends upon the knowledge of their succession and of the periods of their appearance and extinction. If we tabulate the rocks wherewith the past of the elephants is concerned, we may render their arrangement clear thus:

Tertiary Rocks

Recent (Soils etc.)
Post-Pliocene (Ice Age).