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OF THE NUMBER OF TEETH. 57
the lino, or surface of contact, is hollow from behind forwards,
in the Lower-Jaw ; and in the same proportion it is convex in
the Upper-Jaw.
The edge of each row is single at the fore part of the Jaws ;
but as the Teeth grow thicker backwards, it there splits into an
internal and external edge. The canine Tooth, which we shall
call Cuspidatus, is the point from which the two edges go off
so that the first grinder, or what we shall call the first Bicuspis,
is the first Tooth that has a double edge.
OF THE NUMBER OF TEETH.
Their number in the whole, at full maturity, is from twenty-
eight to thirty-two : I once saw twenty-seven only, never more
than thirty-two. Fourteen of them are placed in each Jaw,
when the whole number is no more than twenty-eight; and
sixteen, when there are thirty-two. If the whole be twenty-
nine or thirty-one in number, the Upper-Jaw sometimes, and
sometimes the Lower, has one more than the other ; and when
the Number is thirty, I find them sometimes divided equally
between the two Jaws ; and in other subjects sixteen of them
are in one Jaw, and fourteen in the other. In speaking of the
Number of Teeth, I am supposing that none of them have been
pulled out, or otherwise lost ; but that there are from eight to
twelve of those large posterior Teeth, which I call Grinders, and
that they are so close planted as to make a continuity in the
circle : and in this case, when the number is less than thirty-
two, the deficiency is in the last grinder, (a)
restricted to the maxillary, premaxillary, and inferior maxillary bones.
They form a single row in each jaw, and in most Mammals, as in Man,
occupy each of the above-mentioned bones. They may, however,
project only from the premaxillary bones, as in the Narwhal ; or only
from the lower maxillary bone, as in Ziphius ; or be implanted only in
the superior and inferior maxillaries, and not in the premaxillaries, as
in the true Ruminantia and most Bruta (Sloths, Armadillos, Orycte-
ropes). (1)]
(a) [The normal number of the permanent teeth in Man is thirty-two.
(1) Owen on the Characters of the Class Mammalia,— Journal Tioc. Lin.
Soc, vol. ii., p. 6.
OF THE NUMBER OF TEETH. 57
the lino, or surface of contact, is hollow from behind forwards,
in the Lower-Jaw ; and in the same proportion it is convex in
the Upper-Jaw.
The edge of each row is single at the fore part of the Jaws ;
but as the Teeth grow thicker backwards, it there splits into an
internal and external edge. The canine Tooth, which we shall
call Cuspidatus, is the point from which the two edges go off
so that the first grinder, or what we shall call the first Bicuspis,
is the first Tooth that has a double edge.
OF THE NUMBER OF TEETH.
Their number in the whole, at full maturity, is from twenty-
eight to thirty-two : I once saw twenty-seven only, never more
than thirty-two. Fourteen of them are placed in each Jaw,
when the whole number is no more than twenty-eight; and
sixteen, when there are thirty-two. If the whole be twenty-
nine or thirty-one in number, the Upper-Jaw sometimes, and
sometimes the Lower, has one more than the other ; and when
the Number is thirty, I find them sometimes divided equally
between the two Jaws ; and in other subjects sixteen of them
are in one Jaw, and fourteen in the other. In speaking of the
Number of Teeth, I am supposing that none of them have been
pulled out, or otherwise lost ; but that there are from eight to
twelve of those large posterior Teeth, which I call Grinders, and
that they are so close planted as to make a continuity in the
circle : and in this case, when the number is less than thirty-
two, the deficiency is in the last grinder, (a)
restricted to the maxillary, premaxillary, and inferior maxillary bones.
They form a single row in each jaw, and in most Mammals, as in Man,
occupy each of the above-mentioned bones. They may, however,
project only from the premaxillary bones, as in the Narwhal ; or only
from the lower maxillary bone, as in Ziphius ; or be implanted only in
the superior and inferior maxillaries, and not in the premaxillaries, as
in the true Ruminantia and most Bruta (Sloths, Armadillos, Orycte-
ropes). (1)]
(a) [The normal number of the permanent teeth in Man is thirty-two.
(1) Owen on the Characters of the Class Mammalia,— Journal Tioc. Lin.
Soc, vol. ii., p. 6.
