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102 HUNTER ON THE TEETH.
They are placed under the posterior part of the Maxillary
Sinus, and there the parts which compose the Sinus are thicker
than in the middle. The variations as to the natural number
of the Teeth, depend commonly upon these Dcntes Scqricntiw. (p)
tooth is formed of dentine, thickly coated with dense and brittle enamel.
A thin covering of cement is continued from the fang upon the crown,
but it does not fill up the interspaces of the divisions of the crown as in
the Elephant. In the Mastodons, there were three deciduous molars
(d. m, 2, 3, and 4) on each side, in both jaws ; the second was replaced
by one premolar (p. 3), ami there were three true molars on each side,
both above and below. The grinders of the Proboscidians follow each
other, from before backwards, at long intervals, and are never simultane-
ously in place. In the Mastodons not more than three were in use at
any period on one side of either jaw ; all the molars, save the penul-
timate, were shed by the time the last molar had cut the gum, and in
the old Mastodon, the dentition was at last reduced to m. 3 on each side of
3 '
both jaws. In the existing Elephants, the grinders are d. m. -?/ m.
no premolar replaces either of the deciduous molars. The grinding
teeth are large and complex, and there is never more than one, or two
partially, in place and use at the same time. The series is constantly
in progress of growth and destruction, shedding and replacement. No
premolar succeeding the deciduous molars, all the grinding teeth follow
each other horizontally from behind forwards. The structure of the
Elephants tooth has been before described (Vide note 1., p. 192, vol. iii.)
In the extinct species which, at one time, was a denizen o! Northern
Europe and Asia—the Mammoth (Elephas primigenius), the enamelled
plates were more numerous in proportion to the size of the crown, and
thinner than in the existing Asiatic species. In the African Elephant,
on the other hand, the plates of enamel-covered dentine are fewer and
thicker : they expand from the margins to the centre of the tooth, and
present a lozenge form when worn down by mastication. The final
blending of the plates by a common base of dentine does not take place
simultaneously along the whole extent of the tooth in the Indian
Elephant ; the anterior plates which are first formed, are worn down,
and the base of dentine is exposed, whilst the posterior divisions of the
crown are still distinct, adhering only by cement. The African
Elephant, by the complete basal confluence of the plates before the
anterior ones are worn out, manifests a closer affinity to the Mas-
todon. (1)
(p) [In the Melanian varieties of Man, the molar teeth are of large size,
and the fangs of the wisdom and penultimate molars are not, as a rule,
connate or conjoined. The great size of the molar teeth is most
(1) Professor Owen, Article Odontology, Enyclopsedia Britanmca, Sth edit.
102 HUNTER ON THE TEETH.
They are placed under the posterior part of the Maxillary
Sinus, and there the parts which compose the Sinus are thicker
than in the middle. The variations as to the natural number
of the Teeth, depend commonly upon these Dcntes Scqricntiw. (p)
tooth is formed of dentine, thickly coated with dense and brittle enamel.
A thin covering of cement is continued from the fang upon the crown,
but it does not fill up the interspaces of the divisions of the crown as in
the Elephant. In the Mastodons, there were three deciduous molars
(d. m, 2, 3, and 4) on each side, in both jaws ; the second was replaced
by one premolar (p. 3), ami there were three true molars on each side,
both above and below. The grinders of the Proboscidians follow each
other, from before backwards, at long intervals, and are never simultane-
ously in place. In the Mastodons not more than three were in use at
any period on one side of either jaw ; all the molars, save the penul-
timate, were shed by the time the last molar had cut the gum, and in
the old Mastodon, the dentition was at last reduced to m. 3 on each side of
3 '
both jaws. In the existing Elephants, the grinders are d. m. -?/ m.
no premolar replaces either of the deciduous molars. The grinding
teeth are large and complex, and there is never more than one, or two
partially, in place and use at the same time. The series is constantly
in progress of growth and destruction, shedding and replacement. No
premolar succeeding the deciduous molars, all the grinding teeth follow
each other horizontally from behind forwards. The structure of the
Elephants tooth has been before described (Vide note 1., p. 192, vol. iii.)
In the extinct species which, at one time, was a denizen o! Northern
Europe and Asia—the Mammoth (Elephas primigenius), the enamelled
plates were more numerous in proportion to the size of the crown, and
thinner than in the existing Asiatic species. In the African Elephant,
on the other hand, the plates of enamel-covered dentine are fewer and
thicker : they expand from the margins to the centre of the tooth, and
present a lozenge form when worn down by mastication. The final
blending of the plates by a common base of dentine does not take place
simultaneously along the whole extent of the tooth in the Indian
Elephant ; the anterior plates which are first formed, are worn down,
and the base of dentine is exposed, whilst the posterior divisions of the
crown are still distinct, adhering only by cement. The African
Elephant, by the complete basal confluence of the plates before the
anterior ones are worn out, manifests a closer affinity to the Mas-
todon. (1)
(p) [In the Melanian varieties of Man, the molar teeth are of large size,
and the fangs of the wisdom and penultimate molars are not, as a rule,
connate or conjoined. The great size of the molar teeth is most
(1) Professor Owen, Article Odontology, Enyclopsedia Britanmca, Sth edit.
