190 ANTHROPOLOGY. 



The parotid gland is the largest, and, like the rest, of a pink color. It 

 fills up the cavity on the side of tlie head between the mastoid process and 

 the i-arnus of the lower jaw, extending beyond the edge of the latter, so as 

 to cover the posterior margin of the masseter muscle. It reaches vertically 

 downwards from the zygoma above to the angle of the jaw below. It has 

 no appropriate capsule, but is covered by the processes from the superficial 

 fascia of the neck. Its duct, called the duct of Steno, traverses the outer 

 face of the masseter muscle, in a line drawn from the lobe of the ear to the 

 tip of the nose. It is about the size of a crow-quill, and perforates the pos- 

 terior part of the buccinator muscle so as to have its oral orifice opposite 

 the second large molar tooth of the upper jaw. A small accessory gland is 

 sometimes found between this duct and the zygoma. 



The submaxillary gland is about one third the size of the parotid, and is 

 so situated as to be bounded externally by the body of the lower jaw, 

 superiorly by the mylo-hyoid muscle, and inferiorly by the tendon of the 

 digastric. Its duct {ductus Whartonianus) terminates by a small projecting 

 orifice on the anterior margin of the frajnum of the tongue. 



The sublingual gland is an oblong body, visible on turning up the tongue, 

 where it is seen as a projecting ridged substance on the under surface of 

 the tongue. Instead of a single excretory duct, it has several, sometimes 

 twenty. Occasionally, several of them are collected into one or two prin- 

 cipal trunks {ductus Riviniani), which open either directly into the mouth 

 or into the duct of Wharton. The position of the salivary glands is such 

 that they are pressed upon during mastication, by which means their 

 salivary secretion is expressed. All consist of a congeries of smaller glands 

 or lobes and lobules. The arteries which supply them are branches from 

 the external carotid. Their nerves come from the fifth pair, and from the 

 portio dura. 



The to7isik, or amygdala^ situated one on each side, between the half 

 arches of the palate, constitute a series of mucous glands of irregular figure. 

 They are very vascular, and secrete a viscid fluid, which serves to lubricate 

 the food in its downward passage. 



PL 129, ßg. 29, salivary glands: ', sterno-cleido-mastoid ; ", masseter 

 muscle; ', parotid gland; % accessory parotid; ', single glandules distri- 

 buted about its duct near the end ; °, genio-glossus ; ', mylo-hyoid ; ', exter- 

 nal, ', internal portion of the submaxillary gland; '°, ductus Whartoni; 

 ", upper maxillary ganglion ; ", sublingual gland. 



6. The Pharynx is a large membranous cavity, placed between the 

 cervical vertebrae and the posterior part of the nose and mouth. By means 

 of numerous attachments on all sides, it is prevented from collapsing, and 

 it is drawn up and down in the movements of the tongue and larynx. It 

 consists of three coats, an external, formed by three muscles, the constric- 

 tores pharyngisj inferior^ medius, and superior; an intermediate pharyngeal 

 aponeurosis ; and the internal or lining mucous membrane. This mucous 

 membrane is continuous with that of the mouth, nares, and Eustachian tube, 

 and is continued inferiorly as a lining to the larynx and trachea in front 

 and to the oesophagus behind. It is studded with numerous mucous glands. 

 896 



