THE SALIVARY GLANDS 417 



From its lower border a conical process depends, the uvula, 

 from whose base descend the pillars of the soft palate, the 

 anterior, formed by the palatoglossi muscles, to the sides of 

 the base of the tongue; the posterior, formed by the palato- 

 pharyngci, to the sides of the pharynx. These pillars are covered 

 by mucous membrane and separated below by the tonsil, the 

 space being called the isthmus of the fauces. The muscles of 

 the soft palate are five on each side, and lie in the following 

 relative position from before backward: The palatoglossus, 

 tensor palati, anterior fasciculus of palatopharyngeus, levator 

 palati, azygos uvulae, and lastly the posterior fasciculus of the 

 palatopharyngeus . 



The tonsils (tonsilla palatina) are two in number, situated 

 on each side of the fauces, and lie between the anterior and 

 posterior palatine pillars, and are about J inch long and \ 

 inch wide and thick, but vary much in size. Externally they 

 are separated by the superior constrictors from the internal 

 carotid artery, which is about 1 inch away from it, also lies 

 to the outer side, and ascending pharyngeal arteries; internally 

 they project into the fauces, and present 12 or more orifices 

 which lead into the crypts in their substance. Around the 

 crypt walls are numerous lymphoid follicles consisting of 

 adenoid tissue. The arteries supplying the tonsil are: The 

 dorsalis linguse, a branch of the lingual; the ascending palatine 

 and tonsillar from the facial; the ascending pharyngeal from 

 the external carotid; the descending palatine, a branch of the 

 internal maxillary, and a small meningeal branch. The veins 

 empty into the internal jugular or facial vein, after passing 

 from the tonsillar plexus (on the external surface of the tonsil), 

 to the pharyngeal plexus, then the pterygoid plexus. The 

 lymphatic vessels drain into the submaxillary and retro- 

 pharyngeal nodes and thence to the deep carotid nodes. The 

 nerves of the tonsil are the filaments derived from the tonsillar 

 plexus, formed by branches from the glossopharyngeal joining 

 with branches of the pharyngeal plexus. 



THE SALIVARY GLANDS 



There are three pairs, parotid, submaxillary, and sublingual. 



The parotid gland, the largest, weighs J to 1 ounce, and 



lies on the face below and in front of the ear. Its outer surface, 



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