thirty-two in all. The
internal incisors are larger than the external pair, in the upper jaw,
smaller than the external pair, in the lower jaw. The crowns of the
upper molars exhibit four cusps, or blunt-pointed elevations, and a
ridge crosses the crown obliquely, from the inner, anterior cusp to the
outer, posterior cusp (Figure 17 m2). The anterior lower molars have
five cusps, three external and two internal. The premolars have two
cusps, one internal and one external, of which the outer is the higher.

In all these respects the dentition of the Gorilla may be described in
the same terms as that of Man; but in other matters it exhibits many and
important differences (Figure 17).

Thus the teeth of man constitute a regular and even series--without any
break and without any marked projection of one tooth above the level of
the rest; a peculiarity which, as Cuvier long ago showed, is shared by
no other mammal save one--as different a creature from man as can well
be imagined--namely, the long extinct 'Anoplotherium'. The teeth of
the Gorilla, on the contrary, exhibit a break, or interval, termed the
'diastema', in both jaws: in front of the eye-tooth, or between it and
the outer incisor, in the upper jaw; behind the eyetooth, or between
it and the front false molar, in the lower jaw. Into this break in the
series, in each jaw, fits the canine of the opposite jaw; the size of
the eye-tooth in the Gorilla being so great that it projects, like a
tusk, far beyond the general level of the other teeth. The roots of the
false molar teeth of the Gorilla, again, are more complex than in Man,
and the proportional size of the molars is different. The Gorilla has
the crown of the hindmost grinder of the lower jaw more complex, and
the order of eruption of the permanent teeth is different; the permanent
canines making their appearance before the second and third molars in
Man, and after them in the Gorilla.

Thus, while the teeth of the Gorilla closely resemble those of Man in
number, kind, and in the general pattern of their crowns, they exhibit
marked differences from those of Man in secondary respects, such as
relative size, number of fangs, and order of appearance.

But, if the teeth of the Gorilla be compared with those of an Ape, no
further removed from it than a 'Cynocephalus', or Baboon, it will be
found that differences and resemblances of the same order are easily
observable; but that many of the points in which the Go