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two jaws are not in contact ; nor are the condyles of the
lower jaw, so far back in the temporal cavities as they
can go.

SECTION V.*
OP THE INCREASE OF THE JAWS.

In a fetus three or four months old, the rudiments of the
teeth are placed nearly regular, but as they increase more
rapidly than the arch of the jaws, we find some of them at
birth as it were, pressed out of the circle for want of room,
particularly the cuspidati ; so that the sockets of the lateral
incisores, and those of the anterior grinders nearly come in
contact. However, the jaws gradually accomodate them-
selves to the teeth, and increase at this part nearly in pro-
portion to the size of the cuspidati, becoming again regular,
for indeed we seldom or ever meet with temporary teeth
irregular. This Mr. Hunter allows, but says,f " The jaw
still increases in all points till twelve months after birth, when
the bodies of the six teeth are pretty well formed, but it
never after increases in length between the symphysis and
the sixth tooth ; and from this time too, the alveolar process
which makes the anterior part of the arches of both jaws,
never becomes a section of a larger circle ; and after this
time the jaws lengthen only at their posterior ends." Mr.
Hunter supposed, as the temporary grinders are larger than
the bicuspides which succeed them, that the difference in
size of these would be sufficient to allow the permanent in-

RJake, Essay on the Teeth, in Man, &c. pages 47 to 55.
t Natural History, page 102.