MUSCLES OF THE PALATE. 499 



and being continued from the posterior margin of the hard pa- 

 late, it is stretched across the back of the mouth from one side to 

 the other, and obliquely downwards and backwards. Its inferior 

 margin, which is free, offers in its centre a projection of half an 

 inch or three quarters in length, which is the Uvula. From each 

 side of the latter there proceed two crescentic doublings of the 

 lining membrane of the- mouth, called the lateral half arches of 

 the palate. 



The Anterior Half Arch is more distinct than the other, and 

 arising at the side of the uvula by one end, terminates by the 

 other in the side of the base of the tongue on a line with the 

 papillse maximse. 



The Posterior Half Arch arises from the side of the uvula near 

 the last, and diverging from it backwards, and outwards, has the 

 other end lost gradually in the lining membrane of the pharynx 

 near its middle. In the depression between these duplications, 

 on either side, is the Tonsil Gland. The space bounded in front 

 and behind by these lateral half arches is the Fauces, and the 

 anterior opening into it, is the Isthmus of the Fauces. 



When the mucous membrane of the soft palate is removed, its 

 muscles are exposed, and are as follow : 



1. The Constrictor Isthmi Faucium is a small fasciculus of 

 fibres, on each side, within the duplicature of the anterior lateral 

 half arch. It arises from the middle of the soft palate near the 

 base of the uvula, and is inserted into the side of the tongue near 

 its root in a line with the papillae maxima?. 



It tends to close the opening between the mouth and the pha- 

 rynx. 



2. The Palato-Pharyngeus is also a small fasciculus, within 

 the duplicature forming the posterior lateral half arch. It arises 

 from the middle of the soft palate near the base of the uvula, 

 and is inserted into the pharynx at the space between the mid- 

 dle and lower constrictors, behind the stylo-pharyngeus, and into 

 the superior posterior margin of the thyroid cartilage. It spreads 

 itself out considerably, so as to cover, along with the stylo-pha- 

 ryngeus, almost the whole lateral portion of the pharynx to its 

 lower part. 



It draws the soft palate downwards. 



