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132 ANAT03IY.
is nearly oval in shape, being slightly broader above than below (see
Fig. 65).
The surface of the facial region is extremely irregular, presenting as
it does the orifices to several large cavities which protect three of the
organs of special sense—viz. that of sight, of smell, and of taste. This
region is divided into three portions—one central and two lateral.
The Central Portion commences a little above the nasal eminence,
situated between the internal angular processes of the frontal bone.
This eminence marks the position of the frontal sinuses.
Below the nasal eminence is a semicircular suture uniting the superior
maxilla and nasal bones with the frontal bone.
Directly under this suture is the bridge-roof or arch of the nose. It
is formed by the nasal bones and the nasal processes of the superior
maxillte. It is convex from side to side, and concave from above down-
ward. The median line of this arch presents the internasal suture,
while its lateral surfaces are marked by the naso-maxillary sutures.
The nasal arch is generally pierced by a foramen on either side for
the passage of a vein.
Below the arch of the nose are situated the anterior openings to the
nasal chambers. Conjointly, they are pyriform in shape, bounded
above by the inferior border of the nasal bones, the lateral and inferior
boundaries being formed by the superior maxillse. . The borders of this
opening are sharp and give attachment to the lateral cartilage of the
nose.
Beneath the anterior opening to the nasal chambers are situated the
two incisive fossae, between which will be found the intermaxillary
suture.
Continuing downward, are next found the four incisor teeth, situated
in the alveolar border of the intermaxillary bone.
Below this, in the median line of the inferior maxilla, will be found
the four inferior incisor teeth and the symphysis menti, a slight vertical
ridge at its commencement, but as it passes outward and downward
diverging to form the mental process or chin, a feature characteristic of
man alone. On each side of the upper portion of the ridge are the
inferior incisive fossae.
The Lateral Portions of the face commence above in the frontal
eminences. These eminences are rarely of the same size on both sides
of the forehead. Below the frontal eminence is a depression situated
just above the superciliary ridge. Beneath this depression is the large
circular opening to the orbital cavity. This cavity is bounded above
by the Supraorbital Arch, which extends superiorly from the internal
to the external angular jiroccsscs of the frontal bone.
The inner tiiird of this l)()uudary is marked by a notch or foramen,
the Supraorbital Notch or Foramen, for the passage of the frontal nerve
and vessels. The inferior boundary of the orbital cavity is formed
externally by the malar bone, below by the superior maxilla, and
internally by the nasal process of the superior maxilla and the lachrymal
bone.
The Infraorbital Foramen is below the infraorbital border, and aifords
exit to the nerve and artery of the same name. It is internal to the