PALATAL REGION. 343 



on the outer side of the preceding, 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, its origin extending 

 as far back as the spine of the sphenoid ; it also arises from the anterior aspect 

 of the cartilaginous portion of the Eustachian tube ; descending vertically be- 

 tween the internal pterygoid plate and the inner surface of the Internal Ptery- 

 goid 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 por- 

 tion then passes horizontally inwards, and expands into a broad aponeurosis 

 on the anterior surface of the soft palate, which unites in the median line with 

 the aponeurosis of the opposite muscle, the fibres being attached in front to 

 the transverse ridge on the posterior border of 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 the 

 internal pterygoid plate. In the soft palate, its aponeurotic expansion is an- 

 terior to that of the Levator Palati, being covered by mucous membrane. 



The Azygos Uvulae is not a single muscle, as implied by 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 mucous membrane. 



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

 soft palate throughout nearly the 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 forwards and outwards in front of the tonsil, is inserted into the side 

 and dorsum of the tongue, where it blends with the fibres of the Stylo-glossus 

 muscle. 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 preceding 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. The anterior fasciculus, the thickest, enters the soft palate between the 

 Levator and Tensor, and joins in the middle line the corresponding part of the 

 opposite muscle ; the posterior fasciculus lies in contact with the mucous mem- 

 brane, and also joins with the corresponding muscle in the middle line. Passing 

 outwards and downwards behind the tonsil, the Palato-pharyngeus joins the 

 Stylo-pharyngeus, and is inserted with that muscle into the posterior border of 

 the thyroid cartilage, some of its fibres being lost on the side of the pharynx, 

 and others passing across the middle line posteriorly, to decussate with the 

 muscle of the opposite side. 



Relations. In the soft palate, its anterior and posterior surfaces are covered 

 by mucous membrane, from which it is separated by a layer of palatine glands. 

 By its superior border, it is in relation with the Levator Palati. Where it forms 

 the posterior pillar of the fauces, it is covered by mucous membrane, excepting 

 on its outer surface. In the pharynx it lies between the mucous membrane and 

 the constrictor muscles. 



Nerves. The Tensor Palati is supplied by a branch from the cttc ganglion , 



