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OF THE INCISOKES. *"»^
( 'uspidabi, but pretty much of the same length with all the
other Teeth of this Jaw. (c)
In the Upper-Jaw they are broader and thicker, especially
: their length is nearly the same with those of the
the two first
Lower-Jaw. They stand a little obliquely, with their bodies
turned much more forwards (the first especially) and they gene-
rally fall over those of the Under-Jaw.
The two first Incisores cover the two first, and half of the
second of the Lower-Jaw, so that the second Incisor in the

downwards and backwards ; the base, like that of the tusk of the
Elephant and Mastodon, is widely excavated for a persistent pulp. No
corresponding teeth have been discovered in the upper jaw. In the
existing Proboscideans, two deciduous tusks in the upper jaw, replaced
by a pair of permanent tusks of large size, are the sole representatives
of incisors ; but in the extinct Mastodons, two lower incisive tusks
were also present, although it is uncertain whether they were pre-
ceded by deciduous teeth. The tusk of the Elephant, meeting no
opponent to its growth, increases to an enormous length, following the
curve originally impressed upon it by the form of its socket. Its
growth may be compared to the abnormal increase of the scalpriform
incisor of the Eodent when accident has deprived it of an opposing
tooth. In the female of the Indian species, the tusk is shorter and
straighter, and less deeply implanted, than in the male. According to
Cuvier, large tusks are present in both sexes in the African Elephant ;
at least, this is the case in certain localities. Professor Owen is of
opinion that the smaller fossil tusks of the Mammoth {Elephas primi
genius) which have been discovered belonged to the females of that
extinct species. (1)]
(e) [A degree of departure from the perpendicular direction in the
incisor teeth, especially in the upper, is a usual concomitant of the
prognathic conformation ; and although most common in the Melanian
races, is occasionally observed in every variety of Man. Amongst the
African nations, the prognathic development of the maxillae, and the
consequent obliquity of implantation of the incisor teeth, appear to be
most remarkably expressed in the tribes of the West Coast. The
Quaiquco race, including the Bushmen and Hottentots, exhibit the
prognathic character in a less degree than do the true Negroes. (2)]

(1) Prof. Owen, Art. Odontology, Encyclopedia Britannica, 8th edit.,
vol. xvi., pp. 440-477.
' On the Teeth in the Varieties of Man,' Dental Review, 1860.
(2)