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. AREOLAR TISSUE, TE^^DONS, AND MUSCLES. 209
obliquely forward a short distance beneath the mucous membrane, it has
its outlet through a small papilla opposite the crown of the second supe-
rior molar tooth.
The Parotid Fascia.—The gland is closely encased in a covering derived
from the deep cervical fascia. The superficial layer of the parotid fascia
is dense and strong, arising posteriorly from the sheath covering the
after jjassing over the gland
sterno-cleido-mastoid muscle ; it is con-
tinuous anteriorly with the sheath of the masseter muscle. Above,
it is attached to the zygomatic arch ; below, to its own deep leaflet.
The Deep Layer of the parotid fascia is neither so strong nor so dense
as its superficial ; below, it is formed from a division of the deep cervi-
cal fascia where it passes beneath the gland to be inserted into the base
of the skull ; it forms the stylo-maxillary ligament, and is connected
with the sheaths of the pterygoid muscles, leaving a space or gap
between the anterior edge of the styloid process and the posterior
border of the external pterygoid muscle. Thus it will be seen that the
gland is tightly bound down upon the outside by a close covering, while
within it is not so. The opening in the deep fascia spoken of above
gives communication between the parotid space and the connective tissue
above the pharynx.
The arteries of the gland are very numerous, consisting of a branch
direct from the external carotid, and branchlets from the divisions of
that trunk in its immediate vicinity, as the internal maxillary, tem-
])oral, transversalis, facial, posterior auricular. The veins follow a sim-
ilar course. The external carotid in passing behind the ramus of the
jaw enters the gland, not at the lowest portion, but at its inner and
anterior surface, and passes slightly backMard and outward, becoming
more superficial as it ascends.
The Ii/mj)hatic glands join those of the deep and superficial parts of
the neck, one or more being found in the substance of the parotid, and
others upon its surface. These glands are liable to become enlarged and
form a species of parotid tumor.
The nerves are derived from the facial, the auriculo-temporal, great
auricular, and the sympathetic plexus of the external carotid artery.
Experiments upon the dog and cat have shown that the cerebro-spinal
nerve-supply to this gland is from the glosso-pharyngeal. In addition
to the above are the lesser superficial petrosal nerve and the otic gan-
glion, the fibres finally l)eing distributed to the gland through a branch
of the auriculo-temporal. The facial nerve passes through the gland,
though not so intimately bound up in its substance as is the carotid artery.
The ^Submaxillary Gland—so named from its position beneath the
maxillary bone—is smaller than the parotid, and weighs about two or
two and a half drachms. It is a muco-salivary gland, derived from
epiblastic structure. The lobules comprising the gland are not held so
tightly together as are those of the parotid, though they are more defined.
The gland is situated below the mylo-hyoid ridge of the inferior maxil-
lary i)one in the submaxillary depression and in the submaxillary triangle
of the neck, which is bounded by the mylo-hyoid ridge of the bone and
a line drawn backward to the digastric groove of the temporal bone
above. The lower boundaries are composed of the posterior and ante-
VOL. I.—
. AREOLAR TISSUE, TE^^DONS, AND MUSCLES. 209
obliquely forward a short distance beneath the mucous membrane, it has
its outlet through a small papilla opposite the crown of the second supe-
rior molar tooth.
The Parotid Fascia.—The gland is closely encased in a covering derived
from the deep cervical fascia. The superficial layer of the parotid fascia
is dense and strong, arising posteriorly from the sheath covering the
after jjassing over the gland
sterno-cleido-mastoid muscle ; it is con-
tinuous anteriorly with the sheath of the masseter muscle. Above,
it is attached to the zygomatic arch ; below, to its own deep leaflet.
The Deep Layer of the parotid fascia is neither so strong nor so dense
as its superficial ; below, it is formed from a division of the deep cervi-
cal fascia where it passes beneath the gland to be inserted into the base
of the skull ; it forms the stylo-maxillary ligament, and is connected
with the sheaths of the pterygoid muscles, leaving a space or gap
between the anterior edge of the styloid process and the posterior
border of the external pterygoid muscle. Thus it will be seen that the
gland is tightly bound down upon the outside by a close covering, while
within it is not so. The opening in the deep fascia spoken of above
gives communication between the parotid space and the connective tissue
above the pharynx.
The arteries of the gland are very numerous, consisting of a branch
direct from the external carotid, and branchlets from the divisions of
that trunk in its immediate vicinity, as the internal maxillary, tem-
])oral, transversalis, facial, posterior auricular. The veins follow a sim-
ilar course. The external carotid in passing behind the ramus of the
jaw enters the gland, not at the lowest portion, but at its inner and
anterior surface, and passes slightly backMard and outward, becoming
more superficial as it ascends.
The Ii/mj)hatic glands join those of the deep and superficial parts of
the neck, one or more being found in the substance of the parotid, and
others upon its surface. These glands are liable to become enlarged and
form a species of parotid tumor.
The nerves are derived from the facial, the auriculo-temporal, great
auricular, and the sympathetic plexus of the external carotid artery.
Experiments upon the dog and cat have shown that the cerebro-spinal
nerve-supply to this gland is from the glosso-pharyngeal. In addition
to the above are the lesser superficial petrosal nerve and the otic gan-
glion, the fibres finally l)eing distributed to the gland through a branch
of the auriculo-temporal. The facial nerve passes through the gland,
though not so intimately bound up in its substance as is the carotid artery.
The ^Submaxillary Gland—so named from its position beneath the
maxillary bone—is smaller than the parotid, and weighs about two or
two and a half drachms. It is a muco-salivary gland, derived from
epiblastic structure. The lobules comprising the gland are not held so
tightly together as are those of the parotid, though they are more defined.
The gland is situated below the mylo-hyoid ridge of the inferior maxil-
lary i)one in the submaxillary depression and in the submaxillary triangle
of the neck, which is bounded by the mylo-hyoid ridge of the bone and
a line drawn backward to the digastric groove of the temporal bone
above. The lower boundaries are composed of the posterior and ante-
VOL. I.—
