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OF THE BICUSPIDES. 79
broad to the point, and is often forked there. (/) All the Teeth
hitherto described often have their points bent, and more particu-
larly the Cu.qndati.
The Enamel passes somewhat farther down externally and
upon the inside, than laterally ; but this difference is not so con-
siderable as in the Incisores, and Cttspidati ; in some indeed it
terminates equally all round the Tooth. They stand almost

a curve concave towards the outer cusp. In some cases the curved groove
in the lower premolar is crossed by a ridge, which extends from the
outer to the inner cusp. The inner cusp in the lower tooth is less
developed than the same tubercle in the upper. (1)]
(l) [The fang of the lower premolar is single, long, sub-compressed,
and conical. In the upper jaw, although at first sight the fang of the pre-
molar might be supposed to be single, an examination of the pulp cavity,
which is bifurcated, shows that it really consists of two connate fangs,
an internal and external, which generally, by a groove on the surface
and by a bifid extremity, evince a tendency to separation. (2) More
rarely, the external and internal fangs are completely separated ; accord-
ing to Mr Nasmyth, this conformation is generally confined to the
anterior upper bicuspid. (3) In some rare and exceptional instances
the Editor has seen the external division of the root of the upper
bicuspid again divided into an anterior and posterior fang, making an
implantation by three fangs—the normal implantation of these teeth in
the Anthropoid Apes. Mr Tomes, in his Lectures on Dental Phy-
siology and Surgery, notices this conformation, and instances a Chinese
pkull in which the upper anterior bicuspid has an implantation by
three fangs, like a molar. (4) Such an anomaly, however, is peculiar to
no race of Man. The Editor has noticed it in the cranium of a
Frenchman, in a North American aboriginal, and in two crania of slaves
from the banks of the Mississippi. He has also seen the division indi-
cated by a deep groove on the external fang of an upper premolar in the
cranium of a Hindoo. In all the instances, save one, which have
fallen under his notice, it was the anterior upper premolar which
displayed this complex implantation. In the exceptional case, the left
posterior upper premolar was implanted by three fangs, the right by
two.

(1) Owen, op. cit.
(2) Ibid.
(3) Nasmyth, Researches on the Teeth, p. 68.
(4) Tomes, Lectures on Dental Physiology and Surgery, p. 13.