I250 A MANUAL OF ANATOMY 



epithelium, but on the pharyngeal surface by ciliated columnar 

 epithelium. The glands, which are racemose or acinous, are especi- 

 ally abundant on the buccal surface beneath the mucous membrane, 

 where they are closely packed together. The aponeurosis is attached 

 anteriorly to the posterior border of the hard palate, and laterally 

 it becomes continuous with the aponeurosis of the pharynx. It 

 affords attachment to portions of the palatal muscles. 



Muscles. — These are arranged in pairs, and are as follows : 

 palato-glossus, palato-pharyngeus, azygos uvulae, levator palati, 

 and tensor palati. 



Palato-glossus (Constrictor Isthmi Faucium) — Origin. — ^The under 

 surface of the palatal aponeurosis, its fibres being continuous across 

 the middle line with those of the opposite muscle. 



Insertion. — ^The back part of the side of the tongue, where its 

 fibres blend with the transverse muscular fibres of the tongue. 



Nerve-supply. — ^The pharyngeal plexus. 



The direction of the muscle is outwards, downwards, and forwards. 



Action. — (z) To depress the side of the soft palate, and (2) to 

 draw the tongue upwards and backwards. The two muscles also 

 approximate the anterior pillars of the fauces. By means of these 

 combined actions, aided by the tongue, the isthmus faucium is 

 closed, and the anterior part of the buccal cavity is shut off 

 from the pharjmx at the commencement of the second stage of 

 deglutition. 



The muscle forms the lowest layer in the soft palate, and it gives 

 rise to the mucous fold, called the anterior pillar of the fauces. 



Palato-pharyngeus — Origin. — By two layers, upper and lower. 

 The upper small layer arises from the aponeurosis of the soft palate 

 above the azygos uvulae, its fibres decussating with those of the 

 opposite side ; and the lower large layer arises from the posterior 

 margin of the hard palate, as well as from the palatal aponeurosis, 

 decussating with its fellow of the opposite side. 



Insertion. — (i) The superior and posterior borders of the ala of 

 the thyroid cartilage, and (2) the lateral and posterior wall of 

 the pharynx, its fibres blending with those of the stylo-pharyngeus. 



The muscle receives an accessory slip from the lower part of 

 the cartilage of the Eustachian tube, which is known as the salpingo- 

 pharyngeus muscle. 



Nerve-supply. — ^The pharyngeal plexus. 



The muscle is directed downwards and backwards. 



Action. — (i) To approximate the posterior pillar of the fauces 

 to its fellow at the commencement of the second act of deglutition, 

 and (2) to elevate the pharynx. 



The muscle gives rise to the mucous fold, called the posterior 

 pillar of the fauces. 



Azygos Uvulae — Origin. — The side of the posterior nasal spine 

 and the adjacent aponeurosis. I 



Insertion. — The submucous tissue of the uvula, having previously 1 

 united with its fellow of the opposite side. 



