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308 ANAT03IY.

Posterior auricular, Stylo-glossal,
Stylo-hyoid, Temporo-facial,
Digastric, Cervico-facial.
The Posterior Auricular Nerve arises from the facial uear the stylo-
luastoid forameu. It passes backward in close apposition to the lateral
border of the posterior belly of the digastric muscle, and then curves
outward and upward bet^^een the ear and the mastoid process of the
temporal bone, where it divides into two branches, auricular and oc-
cipital.
The Auricular Branch passes upward behind the ear, and is distrib-
uted to the retrahens aurem, the small muscles, and the skin on the
back part of the pinna. Occasionally it sends a filament to the atollens
aurem muscle.
The Occipital Branch passes upward in a curved direction along the
superior semicircular line, the posterior boundary of the base of the
skull. It is distributed to the occipital muscle.
The branches of communication of the posterior auricular nerve are
with the great auricular and the small occipital nerve of the cervical
plexus, and with the auricular branch of the pneumogastric nerve.
The Stj/ln-hi/oid Amerce is a long slender l)ranch which is distributed
to the stylo-hyoid muscle, and interlaces with the sympathetic plexus
of the external carotid artery.
The Dif/astric Nerve frequently arises in conniion with the stylo-hyoid.
It soon divides into two or three small filaments which are distributed
to the posterior belly of the digastric muscle and interlace with the
glosso-pharyngeal nerve near the base of the skull, and occasionally
with the spinal accessory and jjneumogastric nerves.
The Sti/lo-r/lossal Nerve (lingual nerve of Hirschfeld) Ls a long and
exceedingly delicate branch which arises from the facial nerve near the
base of the styloid jn-ocess of the temjwral bone. It passes downward
and forward behind the stylo-pharyngeus muscle to the side of the
jiharynx and the base of the tongue. It receives several branches of
communication from the glosso-pharyngeal nerve, and is distributed to
the stylo-glossus and palato-glossus muscles, being lost in the mucous
membrane at the base of the tongue.
The Temporo-facial Division of the seventh nerve is the larger of its
two terminals. It passes forward and upward in the substance of the
parotid gland on a level with the neck of the lower jaw. The exter-
nal carotid artery and the temporo-maxillary vein are situated to its
inner side. At the neck of the lower jaw the nerve breaks up into
three branches, temporal, malar, and infraorbital. Before it branches,
however, it receives filaments of communication from the auriculo-
tem]>oral nerve. After its division it receives conununicating branches
from the fifth nerve. The temporo-facial nerve and its conmiunicat-
ing branches, together with numerous small branches from its three
main divisions, form an irregular network of nerves known as the pes
anserinus.
The Temporal Branch ]iasses upward over the zygoma nearly at right
angles to it, and soon breaks u]) into numerous Ijranches which are dis-
tributed to the region of the tem])le and side of the forehead, including