THE ORGANS OF DIGESTION 183 



The soft palate, consisting of muscles, aponeurosis, vessels, 

 nerves, etc., enclosed between two layers of mucous mem- 

 brane, is attached in front to the posterior margin of the 

 hard palate, the sides blending with the pharynx ; from the 

 middle of the posterior edge the uvula projects, and from the 

 bases of this arch, on each side, there are two folds of mucous 

 membrane enclosing muscular fibres the pillars, anterior and 

 posterior, between which the tonsil lies. The narrowed 

 passage between the anterior pillars, leading from the mouth 

 to the pharynx, is called the isthmus faucium. 



The aponeurosis of the soft palate is attached to the posterior 

 edge of the hard palate, is joined by the tendon of the tensor 

 palati, and becomes lost between the muscles. 



Structure of the palate from before backwards : 



1. Oral mucous membrane and mucous glands. 



2. Palato-glossus. 



3. Aponeurosis. 



4. Tensor palati. 



5. Anterior fibres of palato-pharyngeus. 



6. Levator palati. 



7. Azygos uvulae in middle line. 



8. Posterior fibres of the palato-pharyngeus. 



9. Mucous glands and pharyngeal mucous membrane. 

 The tonsils occupy the recesses between the pillars of the 



fauces, the anterior pillar being formed by the palato-glossus 

 and the posterior by the palato-pharyngeus. On the outer 

 side of each is the superior constrictor, and internally the 

 buccal mucous membrane. Their arterial supply is large, 

 from the ascending pharyngeal, ascending and descending 

 palatine, tonsiilar, and dorsalis linguae arteries. 



THE SALIVARY GLANDS. 



The PAROTID GLAND is the largest, and lies between the 

 external auditory meatus and mastoid process behind, and 

 the vertical ramus of the jaw in front. Anteriorly, it overlaps 

 the hinder part of the masseter. 



Boundaries : 



