DEGLUTITION. 



203 



transverse and opposite the cornua of the hyoid bone, with its smallest por- 

 tion at the opening into the oesophagus. Its length is about four and a half 

 inches (11-43 cen- 

 timetres), 

 connected 



It is 

 superi- 

 orly and posterior- 

 ly with the basilar 

 process of the oc- 

 cipital bone and 

 with the upper cer- 

 vical vertebrae. It 

 is incompletelysep- 

 arated from the 

 cavity of the mouth 

 by the velum pen- 

 dulum palati, a 

 movable, musculo- 

 membranous fold 

 continuous with 

 the roof of the 

 mouth and marked 

 by a line in the 

 centre, which in- 

 dicates its original 

 development by 

 two lateral halves. 

 This, which is 

 called the soft 

 palate, when re- 

 laxed, presents a 

 concave surface 

 looking toward 

 the mouth, a free, 



arched border, and a conical process hanging from the centre, called 

 the uvula. On either side of the soft palate, are two curved pillars, or 

 arches. 



The anterior pillars of the fauces are formed by the palato-glossus muscle 

 on either side and run obliquely downward and forward, the mucous mem- 

 brane which covers them becoming continuous with the membrane over the 

 base of the tongue. The posterior pillars are more closely approximated to 

 each other than the anterior. They run obliquely downward and backward, 

 their mucous membrane becoming continuous with the membrane covering 

 the sides of the pharynx. Between the lower portion of the anterior and 

 posterior pillars, are the tonsils ; and in the substance of and beneath the 

 mucous membrane of the palate and pharynx, are small glands, which have 

 already been described. 



FIG. 55. Cavities of the mouth and pharynx, etc. (Sappey). 

 Section, in the median line, of the face and the superior portion of the neck, 

 designed to show the mouth in its relations to the nasal fossse, the phar- 

 ynx and the larynx : 1. sphenoidal sinuses ; 2, internal orifice of the Eu- 

 stachian tube ; 3, palatine arch ; 4, velum pendulum palati ; 5, anterior 

 pillar of the soft palate ; 6, posterior pillar of the soft palate : 7, tonsil ; 

 8, lingual portion of the cavity of the pharynx ; 9, epiglottis ; 10, section 

 of the hyoid bone ; 11, laryrigeal portion of the cavity of the pharynx; 

 12, cavity of the larynx. 



