422 THE MUSCLES AND FASCIJE. 



of the Superior constrictor, it passes obliquely downward and inward, its fibres 

 spreading out in the soft palate as far as the middle line, where they blend with 

 those of the opposite side. 



Relations. Externally, with the Tensor palati and Superior constrictor; 

 internally, with the mucous membrane of the pharynx ; posteriorly, with the 

 posterior fasciculus of the Palato-pharyngeus, the Azygos uvulae, and the mucous 

 lining of the soft palate. 



The Circumflexus or Tensor palati is a broad, thin, ribbon-like muscle, placed 

 on the outer side of the Levator palati, and consisting of a vertical and a horizontal 

 portion. The vertical portion arises by a broad, thin, and flat lamella from the 

 scaphoid fossa at the base of the internal pterygoid plate ; from the spine of the 

 sphenoid ; the vaginal process of the temporal bone and the anterior aspect of 

 the cartilaginous portion of the Eustachian tube : descending vertically between 

 the internal pterygoid plate and the inner surface of the Internal pterygoid 

 muscle, it terminates in a tendon, which winds round the hamular process, being 

 retained in this situation by some of the fibres of origin of the Internal pterygoid 

 muscle, and lubricated by a bursa. The tendon or horizontal portion then passes 

 horizontally inward, and is inserted into a broad aponeurosis, the palatine 

 aponeurosis, and into the transverse ridge on the horizontal portion of the palate 

 bone. 



Relations. Externally, with the Internal pterygoid; internally, with the 

 Levator palati, from which it is separated by the Superior constrictor, and with 

 the internal pterygoid plate. In the soft palate its tendon and the palatine 

 aponeurosis is anterior to that of the Levator palati, being covered by the Palato- 

 glossus and the mucous membrane. 



Palatine Aponeurosis. Attached to the posterior border of the hard palate is 

 a thin, firm, fibrous lamella which supports the muscles and gives strength to the 

 soft palate. It is thicker above than below, where it becomes very thin and 

 difficult to define. Laterally, it is continuous with the pharyngeal aponeurosis. 



The Azygos uvulae is not a single muscle, as would be inferred from its name, 

 but a pair of narrow cylindrical fleshy fasciculi placed side by side in the median 

 line of the soft palate. Each muscle arises from the posterior nasal spine of the 

 palate bone and from the contiguous tendinous aponeurosis of the soft palate, and 

 descends to be inserted into the uvula. 



Relations. Anteriorly, with the tendinous expansion of the Levatores palati ; 

 behind, with the posterior fasciculus of the Palato-pharyngeus and the mucous 

 membrane. 



The two next muscles are exposed by removing the mucous membrane from the pillars of 

 the soft palate throughout nearly their whole extent. 



The Palato-glossus (Constrictor isthmi faucium) is a small fleshy fasciculus, 

 narrower in the middle than at either extremity, forming, with the mucous 

 membrane covering its surface, the anterior pillar of the soft palate. It arises 

 from the anterior surface of the soft palate on each side of the uvula, and, passing 

 downward, forward, and outward in front of the tonsil, is inserted into the side 

 of the tongue, some of its fibres spreading over the dorsum, and others passing 

 deeply into the substance of the organ to intermingle with the Transversus linguae. 

 In the soft palate the fibres of this muscle are continuous with those of the muscle 

 of the opposite side. 



The Palato-pharyngeus is a long, fleshy fasciculus, narrower in the middle than 

 at either extremity, forming, with the mucous membrane covering its surface, the 

 posterior pillar of the soft palate. It is separated from the Palato-glossus by an 

 angular interval, in which the tonsil is lodged. It arises from the soft palate by 

 an expanded fasciculus, which is divided into two parts by the Levator palati and 

 Azygos uvulae. The posterior fasciculus lies in contact with the mucous membrane, 

 and also joins with the corresponding muscle in the middle line ; the anterior 

 fasciculus, the thicker, lies in the soft palate between the Levator and Tensor, and 



