PAROTID GLAND. 469 



The Salivary Glands. 



The salivary glands have such an intimate connexion with 

 the mouth that they may be described with it.* 



There are three principal glands on each side : the Parotid, 

 Submaxillary, and the Sublingual. They are of a whitish or 

 pale flesh color, and are composed of many small united masses 

 or lobuli, each of which sends a small excretory duct to join 

 similar ducts from the other lobuli, and thereby form the great 

 duct of the gland. 



The Parotid is much larger than the other glands. It 

 occupies a large portion of the vacuity between the mastoid 

 process and the posterior parts of the lower jaw. It extends 

 from the ear and the mastoid process over a portion of the 

 masseter muscle, and from the zygoma to the basis of the lower 

 jaw. Its name is supposed to be derived from two Greek 

 words which signify contiguity to the ear. It is of a firm con- 

 sistence. It receives branches from the external carotid artery 

 and from its facial branch. 



From the anterior edge of this gland, rather above the middle, 

 the great duct proceeds anteriorly across the masseter muscle ; 

 and, after it has passed over, it bends inward through the adipose 

 matter of the cheek to the buccinator muscle, which it perforates 

 obliquely, and opens on the inside of the cheek opposite to the 

 interval between the second and third molar teeth of the upper 

 jaw. The aperture of the duct is rather less than the general 

 diameter of it, and this circumstance has the effect of a valve. 

 When the duct leaves the parotid, several small glandular 

 bodies called sociae parotidis, are often attached to it, and tiieir 

 ducts communicate with it. The main duct is sometimes called 

 ductus stenonianus, after Steno, who first described it. 



When the mouth is opened wide, as in gaping, there is often 

 a jet of saliva from it into the mouth. 



The parotid gland furnishes the largest proportion of saliva. 



It covers the nerve called Portio Dura, after it has emerged 

 from the foramen stylo-mastoideum. 



* For a further account of glands, see General Anatomy of Glandular 

 System. 



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