ng one of the Sea-cows
(_Sirenia_)--though this view has been rendered untenable by
the discovery of limb-bones which can hardly belong to any other
animal, and which are distinctly Proboscidean in type. The most
celebrated skull of the Deinothere (fig. 246) is one which was
exhumed from the Upper Miocene deposits of Epplesheim, in
Hesse-Darmstadt, in the year 1836. This skull was four and a half
feet in length, and indicated an animal larger than any existing
species of Elephant. The upper jaw is destitute of incisor or
canine teeth, but is furnished on each side with five molars,
which are opposed to a corresponding series of grinding teeth in
the lower jaw. No canines are present in the lower jaw; but the
front portion of the jaw is abruptly bent downwards, and carries
two huge tusk-like incisor teeth, which are curved downwards and
backwards, and the use of which is rather problematical. Not
only does the Deinothere occur in Europe, but remains belonging
to this genus have also been detected in the Siwalik Hills, in
India.

[Illustration: Fig. 246.--Skull of _Deinotherium giganteum_, greatly
reduced. From the Upper Micene of Germany.]

The true Elephants (_Elephas_) do not appear to have existed
during the Miocene period in Europe, but several species have
been detected in the Upper Miocene deposits of the Siwalik Hills,
in India. The fossil forms, though in all cases specifically, and
in some cases even sub-generically, distinct, agree with those
now in existence in the general conformation of their skeleton,
and in the principal characters of their dentition. In all, the
canine teeth are wanting in both jaws; and there are no incisor
teeth in the lower jaw, whilst there are two incisors in the
front of the upper jaw, which are developed into two huge "tusks."
There are six molar teeth on each side of both the upper and lower
jaw, but only one, or at most a part of two, is in actual use
at any given time; and as this becomes worn away, it is pushed
forward and replaced by its successor behind it. The molars are of
very large size, and are each composed of a number of transverse
plates of enamel united together by ivory; and by the process
of mastication, the teeth become worn down to a flat surface,
crossed by the enamel-ridges in varying patterns; These patterns
are different in the different species of Elephants, though constant
for each; and they constitute one of the most readily available
means of separat