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Temporary Teeth. 21
des, and these latter teeth are in every respect intermediate
between the cuspidati and the molares. The incisores are
formed for catting the food, the cuspidati for tearing it, the
bicuspides for tearing and grinding, the molares exclusively for
grinding it. The incisores have but one root nearly round,
and the body nearly flat with a cutting edge
; the cuspidati
have also but one root, but it is longer and stronger than that of
the incisores, the body is longer, rounder and its points conical
the bicuspides of the upper jaw have two fangs, separated by a
groove, that of the lower but one ; the body has two points,
and more nearly resembles the molares, which complete the
masticating surface.
On viewing the teeth of both jaws, in their relative situation,
when the mouth is closed, the incisores and cuspidati of the
upper jaw, will be seen to project or rather shut over those of
the lower jaw, so as partially to conceal them ; also that the
external point of the inferior bicuspides will strike within the
two points of those of'the upper jaw.
OF THE FORMATION OF THE TEETH.
The formation of the teeth is a subject interesting to a per-
son fond of natural history ; but as a full desciiption would
occupy too much space for the limits of this work, we shall
merely give a brief outline.
TEMPORARY TEETH.
The rudiments of the temporary teeth can be distinguished
very early in a foetus ; as soon as the organization of its parts
receive a determinate form.
" In a foetus of about four months old, the rudiments of the
teeth may be very distinctly seen ; upon examining those sub-
stances found in the jaws, they are seen to be soft, or pulpy
bodies, bearing a resemblance to the figure of the body of the
tooth to be formed, and each of them is contained in a mem-
brane proper to itself.
Temporary Teeth. 21
des, and these latter teeth are in every respect intermediate
between the cuspidati and the molares. The incisores are
formed for catting the food, the cuspidati for tearing it, the
bicuspides for tearing and grinding, the molares exclusively for
grinding it. The incisores have but one root nearly round,
and the body nearly flat with a cutting edge
; the cuspidati
have also but one root, but it is longer and stronger than that of
the incisores, the body is longer, rounder and its points conical
the bicuspides of the upper jaw have two fangs, separated by a
groove, that of the lower but one ; the body has two points,
and more nearly resembles the molares, which complete the
masticating surface.
On viewing the teeth of both jaws, in their relative situation,
when the mouth is closed, the incisores and cuspidati of the
upper jaw, will be seen to project or rather shut over those of
the lower jaw, so as partially to conceal them ; also that the
external point of the inferior bicuspides will strike within the
two points of those of'the upper jaw.
OF THE FORMATION OF THE TEETH.
The formation of the teeth is a subject interesting to a per-
son fond of natural history ; but as a full desciiption would
occupy too much space for the limits of this work, we shall
merely give a brief outline.
TEMPORARY TEETH.
The rudiments of the temporary teeth can be distinguished
very early in a foetus ; as soon as the organization of its parts
receive a determinate form.
" In a foetus of about four months old, the rudiments of the
teeth may be very distinctly seen ; upon examining those sub-
stances found in the jaws, they are seen to be soft, or pulpy
bodies, bearing a resemblance to the figure of the body of the
tooth to be formed, and each of them is contained in a mem-
brane proper to itself.
