224 HUMAN ANATOMY. 



drawn about a finger's breadth below the zygoma, from the lower 

 part of the ear to midway between the ala of the nose and the 

 margin of the upper lip, to open about the position of the second 

 molar tooth of the upper jaw. 



Its arteries are branches of the external carotid. The veins 

 empty into the external jugular. The lymphatics empty into 

 the superficial and deep cervical glands, and the nerves are 

 derived from the facial, from the superficial temporal branches 

 of the great auricular, the auriculo-temporal, and sympathetic. 



The submaxillary gland occupies the submaxillary fossa on 

 the inferior surface of the inferior maxilla, within the sub- 

 maxillary triangle of the neck. The facial artery grooves its 

 upper and posterior border, and it is separated behind from 

 the parotid gland by the stylo-maxillary ligament. The duct 

 of the submaxillary gland, or Wharton's duct, about two inches 

 in length, passes forward between the hyoglossus, geniohyoglos- 

 sus, and mylohyoid muscles, to open at the side of the frasnmn 

 linguae. 



Its arteries are from the facial and lingual ; the veins follow 

 the course of the corresponding arteries; the nerves are from 

 the submaxillary ganglion, the sympathetic, and the mylohyoid 

 branch of the inferior dental. 



The sublingual gland, the smallest, lies on the floor of the 

 mouth, at the side of the fraenum linguae, beneath the mucous 

 membrane. Its ducts, called the ducts of Bivini, from eight to 

 twenty, open on the mucous membrane. One of them, the 

 longest, called the duct of Bartholin, joins Wharton's duct. Its 

 arteries are from the submental and sublingual. The nerves 

 are branches from the gustatory. 



Besides these glands, the mucous membrane of the mouth is ' 

 plentifully supplied with mucous glands. 



THE PHARYNX is a musculo-membranous sac, extending 

 from the basilar process of the occipital bone above to the level 

 of the fifth cervical vertebra or the cricoid cartilage below. It 

 is about four and a half inches in length. It has communicating 

 with it seven openings: 



Two posterior nares, Larynx, 



Two Eustachian tubes, (Esophagus, 



Mouth. 



It is composed of three coats : 



1. Fibrous coat, or pharyngeal aponeurosis, attached above 

 to the pharyngeal spine of the basilar process of the occipital 

 bone ; it affords attachment in the median line to the constrictor 

 muscles of the pharynx. 



