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134 ANATOMY.
The Anterior Lacerated Foramen is situated near the apex of tlie
orbital cavity, just external to the optic foramen, and extends upward
and outward between the greater and lesser wings of the sphenoid bone.
It transmits from the brain into the orbit the third, fourth, first division
(ophthalmic) of the fifth and sixth nerves, and through the orbit into
the brain the ophthalmic vein and a small artery, a branch of the
lachrymal.
The Anterior and Posterior Ethmoidal Foramina are situated on the
inner wall of the orbital cavity in the ethmo-frontal suture, between the
ethmoid and frontal bones. The anterior foramen transmits from the
orbit into the brain-case the nasal branch of the ophthalmic nerve and
an artery and vein, branches of the ophthalmic, which accompany this
nerve.
The Posterior Foramen transmits from the orbit the posterior eth-
moidal artery and vein.
The Lachrymal Caned is situated at the anterior inferior angle of the
orbital cavity. Its superior orifice is between the nasal process of the
frontal bone and the lachrymal bone. From this point the canal extends
downward, inward, and backward, terminating in the inferior meatus
of the nose. It accommodates the lachrymal duct.
The LnfraorbiUd Canal commences by a groove situated about the
centre of the posterior border of the floor of the orbital cavity. This
groove passes forward and downward into the body of the superior
maxilla, and makes its exit on the face in the infraorbital foramen
below the middle of the infraorbital ridge. It transmits the infra-
orbital nerve, which is a continuation of the second division of the
fifth or superior maxillary nerve, and infraorbital vessels.
The Spheno-maxillari/ Fissure is situated in the posterior portion of
the orbital cavity, extending from the body of the sphenoid bone for-
Avard and outw^ard to the sphenoidal border of the malar bone. It is
bounded in front by the posterior superior border of the superior max-
illa and orbital process of the palate bone, and behind by the inferior
border of the great wing of the sphenoid bone. It transmits from the
brain to the orbit the infraorbital nerve and vessels and branches of
nerves from the spheno-maxillary ganglion.
The Malar Foramina are situated within the orbital cavity on the
orbital surface of the malar bone. They transmit from the orbital
cavity to the cheek and temporal fossa terminal branches of nerves and
vessels. The facial opening is that opening formed by the anterior
borders of the orbit.

The Nasal Fossje.
The Nasal Fossa, two in number, forming the internal nose, are situ-
ated on either side of the niedian line of the face, and extend from the
under surface of the anterior portion of the brain-case superiorly to the
upper surface of the bones fi)rming the hard palate inferiorly, and from
the facial border of the external aperture of the nose anteriorly to the
free border of the internal ]itervgoid plate posteriorly. They are sepa-
rated by a thin partition of bone, the nasal septum, open on the face by