960 THE DIGESTIVE SYSTEM. 
closely to the styloid process. ‘Thus the recess is three-sided (Fig. 646), the third 
side corresponding to the parotid fascia covering the gland. Into this parotid recess the 
greater part of the parotid gland fits closely. From its anterior part, however, the 
variably-developed facial process is continued forward over the masseter muscle. 
Parotid Fascia.—The parotid recess is covered over on the one hand, and lined on the 
other, by fascia. ‘The covering layer is specially known as the parotid fascia, and both it 
and the lining layer are derived from the deep cervical fascia, which divides below to 
enclose the gland. The parotid fascia proper is connected above to the zygoma ; behind, to 
the auditory meatus and anterior border of the sterno-mastoid ; below, it is continuous 
with the deep cervical fascia, and in front it passes forwards over the masseter, and joins 
the fascia of that muscle. The layer of fascia beneath the gland forms « lining for the 
recess, and is united above to the periosteum over the auditory meatus and back part of 
the glenoid fossa ; internally it is connected to the styloid process ; whilst below it joins 
the deep cervical 
fascia. Taken together, 
the two layers form a 
definite capsule which 
completely encloses the 
gland. In connexion 
with the lower and 
anterior part of this 
capsule is developed a 
special flat band, the 
stylo-mandibular liga- 
ment, which passes 
downwards and out- 
wards from the styloid 
process to the angle of 
the jaw. It separates 
the anterior part of the 
parotid gland from the 
back of the internal 
pterygoid muscle ; per- 
haps occasionally, also, 
from the upper and 
posterior part of the 
submaxillary gland. 
Shape and Rela- 
Pht tenege tions of the Parotid 
arton’s duct : 
Nab i andl Gland.—Like the 
Duct of sublingual gland 3 : 5 
recess in which it 
lies, the main mass 
of the parotid gland 
is three-sided (Fig 
The greater portion of the body of the mandible has been removed to expose the aS three x oe - ( o 
sublingual and the deeper parts of the submaxillary glands. Four ducts of 646), the three 
the sublingual gland are shown opening on the floor of the mouth over the surfaces being super- 
gland, a fifth is shown opening into the anterior end of Wharton’s duct. ¢.: a 
DRUMS AMEN Sie cer ta G9 oor ba ee ' ficial, anterior, and 
he course of Wharton’s duct is shown by a dotted line. oar 
posterlor. 
The superficial surface is closely covered by the parotid fascia, and its lower 
part is also crossed by the highest fibres of the platysma. The anterior surface, 
approximately flat, les in contact with the wide posterior surface of the in- 
ternal pterygoid muscle ; it is also related to the posterior border of the mandible 
and the masseter muscle, whilst from its superficial part the facial process is 
continued forwards over that muscle. The posterior surface lies from without 
inwards against (1) the anterior border of the sterno-mastoid and the auditory 
meatus, (2) the posterior belly of the digastric and the occipital artery, and (3) the 
spinal accessory nerve and carotid sheath—the internal jugular vein within the 
sheath being in very close relation. The inner angle formed by the meeting 
of the anterior and posterior surfaces corresponds to the styloid process and the 
styloid muscles (Fig. 646). Above, the gland is limited superficially by the 
zygoma; more deeply a thin process runs up into the posterior part of the glenoid 
Stenson’s duct - 
Orifice of duct 
Parotid gland 
Masseter (cut) 
Mucous membrane 
(cut) 
Deep process of 
submaxillary gland 
Mylohyoid muscle 
(cut) 
Submaxillary gland 
Lower border of 
mandible 
Mylohyoid muscle 
Anterior belly of 
digastric 
Hyoid bone — 
j) =. ; 
| Duct of Bartholin (vare) 
i 
Sublingual gland 
Fic. 647.—THE SALIVARY GLANDS AND THEIR Ducts. 
