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72 HUNTER ON THE TEETH.
The shape of the body of the Cuspidatw may be very well

resembles in form and size a canine but in the upper jaw it is
;
implanted by two roots. In the Tupaias (Glisorex), small canines are
present in both jaws. None of the small premolars which succeed the
incisors in the Shrews fulfil the office, or have the configuration of a
canine. The common Mole (Talpa Europcea), has an upper canine of
large size, with a crown of characteristic shape ; but it is implanted by-
two fangs. The tooth in the lower jaw, which by right of position is
to be considered the canine, is small, simple, and resembles the
incisors ; whilst the first premolar has a laniariform crown, and like the
canine above, has a double implantation. This latter tooth is con-
sidered the canine by Bell and Dr Blainville. In Talpa mooguru the
inferior canine is absent. In the Condylure, or Rayed-Mole, it is pre-
sent, and has the form and proportions of a canine. Canines^are
absent in the lower jaw in the genus Scalops. Neither by virtue o
shape or office are the teeth which succeed the incisors in the Chry-
sochlore to be considered canines.
Canines of normal form are present in both jaws in the Bats. In the
Vampire (Desmodus Vampirus), the canines have large, lancet-shaped
crowns similar to those of the incisors.
The absence of canines is one of tue characteristics of Rodent
dentition.
Order Quadrumaita. In the Aye-aye (Cheiromys), whose dentition
makes a near approach to that of the Rodents, canines are absent. They
are present in the Slow Lemurs (Stenojis), and in the True Lemurs, or
Makis. In the True Lemurs, the inferior canines are compressed, and
procumbent like the incisors. The upper canine tooth is long, curved,
compressed, sharp-edged, and pointed. Canines are present in both
jaws in the Platyrhine, as in the Catarhine Quadrumana. They are
formidable weapons in the Capuchin Monkeys (Cebus). In the Mon-
keys and Apes of the Old World they are always longer than the ad-
joining teeth ; they are pointed, conical, with trenchant posterior mar-
gins. In the males of the great Baboons, Orangs, and Chimpanzees, they
acquire a size and development rivalling that in the typical Carnivora.
Their most formidable development is exemplified in the Mandrill
(Cynocephalus maimon). In the Mandrill, the upper canines descend
behind the crowns of the lower, and along the outside of the first
lower premolars, the crowns of which appear bent back by their action.
Deeply grooved in front, like the poison fangs of some snake3, they
v
have obtained the name of " denies canaliculati, whilst their posterior
margin is very sharp. They are separated by a long interval from the
upper incisors, by a shorter one from the first upper premolar. A com-
parison of the human canines with the same teeth in the Gorilla (see
plate I), Chimpanzee, and Orangs, demonstrates one of the most striking