PAROTID GLAND. 41 



The transverse facial artery (fig. 17) is a branch of the temporal, and 

 appears in the face at the anterior border of the parotid gland. It lies by 

 the side of the parotid duct, with branches of the facial nerve, and dis- 

 tributes offsets to the muscles and integuments ; some branches anastomose 

 with the facial artery. 



Dissection. The parotid gland in front of the ear may be next displayed. 

 To see the gland, raise the skin from the surface towards the ear by means 

 of a cut from the base of the jaw to the anterior border of the sterno-mas- 

 toid muscle ; this cut may be united with that made for the dissection of 

 the posterior muscle of the ear. A strong fascia covers the gland, and is 

 connected above and behind to the zygomatic arch and the cartilage of the 

 ear, but is continued over the face in front; this is to be removed, so that 

 the gland may be detached slightly from the parts around. The great 

 auricular nerve will be seen ascending to the lobe of the ear; and one or 

 two small glands rest on the surface of the parotid. 



The PAROTID (fig. 16, 10 ) is the largest of the salivary glands. It occu- 

 pies the space between the ear and the lower jaw, and is named from its 

 position. Its excretory duct enters the mouth through the middle of the 

 cheek. 



The shape of the gland is irregular, and is determined somewhat by the 

 bounding parts. Thus inferiorly, where there is not any resisting struc- 

 ture, the parotid projects into the neck, and comes into close proximity 

 with the sub-maxillary gland, though separated from it by a process of the 

 cervical fascia; a line from the angle of the jaw to the sterno-mastoid 

 muscle marks usually the extent of the gland in this direction. Above, 

 the parotid is limited by the zygomatic arch and the temporal bone. 

 Along the posterior part the sterno-mastoid muscle extends ; but anteriorly 

 the gland projects somewhat on the face, and in this direction a small 

 accessory part, soda parotidis, is prolonged from it over the masseter. 



Connected with the anterior border is the excretory duct duct of Sten- 

 son (ductus Stenonis, fig. 17), which crosses the masseter below the soda 

 parotidis, and perforates the cheek obliquely opposite the second molar 

 tooth of the upper jaw. The duct lies between the transverse facial artery 

 and some branches of the facial nerve, the latter being below it. A line 

 drawn from the meatus auditorius to a little below the nostril would mark 

 the level of the duct in the face ; and the central point of the line would 

 be opposite the opening into the mouth. The length of the duct is about 

 two inches and a half; and its capacity is large enough to allow a small 

 probe to pass, but the opening into the mouth is much less. 



The cutaneous surface of the parotid is smooth, and one or two lymphatic 

 glands are seated on it ; but from the deep part processes are sent into the 

 inequalities of the space between the jaw and the mastoid process. 



Dissection. By removing with caution the parotid gland, the hollows 

 that it fills will come into view : at the same time the dissector will see 

 the vessels and nerves that pass through it. An examination of the pro- 

 cesses of the gland, and of the number of important vessels and nerves in 

 relation with it, will demonstrate the dangers attending any operation on 

 it. The duct may be opened, and a pin may be passed along it to the 

 mouth, to show the diminished size of the aperture. 



Two large processes of the gland extend deeply into the neck. One 

 dips behind the styloid process, and projects beneath the mastoid process 

 and sterno-mastoid muscle, whilst it reaches also the deep vessels and 

 nerves of the neck. The other piece is situate in front of the styloid 



