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74 HUNTER ON THE TEETH.
so as to end in a narrow point, instead of a thin edge ; and

rately developed, but the anterior longitudinal groove, which is pre-
sent in both species of Troglodytes, is absent.
In the typical genus of the Carnivora—the genus Felis—the canines
are remarkable for their size and development. In the Lion, for instance,
this tooth is of extraordinary strength, deeply implanted by a fang of con-
siderably greater length and thickness than the enamelled crown. The
crown is conical and sharp-pointed, slightly recurved, convex in front,
with one or two grooves on the outer side, almost flat on the inner side,
with a trenchant posterior edge. The canines are proportionately some-
what smaller in the Hyaenas than in the Felidce. In the Viverridce they
are less developed, and their crowns are almost smooth. In the genus
Canis, the enamel-pointed crown forms about half the length of the tooth,
it is curved, sub-compressed, and the surface is uninterrupted by longi-
tudinal depressions. Canines are well developed in the sub-family of
the Badgers (Melidce) : they are well-pointed, with a trenchant, posterior
edge. In the Indian Badger, the crown is more compressed than in the
European. All the Seals (Phocida?) are provided with large and strong
canines. In the great proboscidian and hooded Seals, this tooth attains
very formidable development, especially in the male ; its fang is curved,
thick, and subcpiadrate. Canines are only present in the upper jaw of
the Walrus, but their absence in the lower is fully compensated by the
extraordinary size and development attained by the superior pair. These
teeth grow to an enormous length ; they descend and project from the
mouth like tusks, inclining slightly outwards, and bending backwards.
A transverse section of the tooth presents an oval, with a shallow, longi-
tudinal groove on the inner side, and one or two narrower, longitudinal
impressions on the outer. Its growth being uninterrupted, the base con-
tinues widely open. The tusks of the "Walrus are not merely weapons
of offence and defence, but they are most serviceable in aiding the animal
to clamber over blocks of ice. In a large extinct Carnivore, the Mach-
airodus, the upper canines attained a development almost rivalling that
of the tusks of the Walrus. Their shape, however, as well as the number
and conformation of the other teeth, indicate a close relationship to the
genus Felis. The crown of the Canine in Machairodus is more com-
pressed and trenchant than in the Felidce. It passed outside the lower
jaw when the mouth was closed, as is indicated by a depression on the
outer side of the inferior maxilla, between the canine and first molar.
Both the anterior and posterior edges of this long, falciform tooth are
finely serrated. The lower canine of Machairodus is small, and appears
to form the terminal tooth of the incisor series.
Herbicora.—Amongst the vegetable feeders, the presence of canine
teeth in one or both jaws is by no means constant. Thus, in the hollow-
horned Ruminants, these teeth are invariably absent in the upper jaw.
In many, also, of the solid-horned Ruminants (Cervidce) upper canines