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OF THE URINDERS. 95

the Lower-Jaw, and they are placed further back in the mouth,
so that each is partly opposed to two of the Lower-Jaw. The
second in the Upper-Jaw is smaller than the others, and the

distinctly marked, but the postero-internal tubercle is but feebly deve-
loped. The unworn surfaces of the lower molars are, like those of the
upper, minutely wrinkled. Lastly, it would appear that, in the Orangs>
it is not very unusual to find a fourth supernumerary molar, sometimes
in the upper, sometimes in the lower jaw, on one or both sides. It is
worthy of remark, that supernumerary teeth occurring in the human
subject are generally incisors or canines.
The molar series in the true Carnivora presents a peculiar type. Its
number varies in different genera, and the typical characters are most
strongly marked in those which exhibit most strongly carnivorous pro-
pensities. . In the
, m. $ [ f"
The formula in the Felidce is p. § [ -f I
upper jaw, the first premolar (p. 2) is small and rudimentary ; the
second (p. 3) is much larger, implanted by two fangs, with a trenchant,
conical crown, having its cutting edge slightly notched, indicating a
division into three lobes, with a posterior basal ridge ; the third (p. 4) is
the upper "dent carnassiere " of Cuvier—the scissor, or sectorial tooth.
It is a large tooth, implanted by two fangs. The crown consists of a
trenchant portion (the blade) which is divided into three lobes, of which
the anterior is the smallest, the middle the longest and most pointed,
and the posterior largest. On the inner side of the base of the anterior
third of the crown, a thick tubercle is developed, which projects inwards.
The two posterior thirds of the inner surface of the crown are smooth,
and against this smooth portion works the outer surface of the blade of
the lower carnassiere. The fourth tooth (m. 1) is small and rudimentary.
It is implanted behind and on the inner side of the carnassiere. In
the lower jaw, the premolar series is reduced to two by the absence of
p. 2. Of the two premolars, the anterior is the smaller. They have
both compressed, trenchant, conical crowns, divided by slight indenta-
tions in the cutting edge into three lobes, of which the middle is the
largest. The second (p. 4) has a posterior basal ridge. The third tooth
is the lower carnassiere—the first molar. It is implanted by two fangs,
and its crown is nearly equally divided into two trenchant lobes. It is
to be remembered that the upper carnassiere in the Carnivora always
succeeds a deciduous tuberculate molar—it is, therefore, essentially a
premolar ; whilst the lower carnassiere is developed behind the deci-
duous series—it is, therefore, the first true molar. The upper carnassiere
is always a little anterior to the lower. In the Hyamas, the molar formula
is P' ¥. %. m - t. t. • The teeth of the molar series in both jaws are
larger and stronger than in the Felidce, and an additional premolar tooth,
p. 1 in the upper, p. 2 in the lower jaw, is retained. As in the Felidce,
the upper true molars are rudimentary. The premolars are remark-