THE PALATAL REGION. 423 



joins in the middle line the corresponding part of the opposite muscle. Passing 

 outward and downward 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. 



The Salpingo-pharyngeus. This muscle arises from the inferior part of the 

 Eustachian tube near its orifice ; it passes downward and blends with the posterior 

 fasciculus of the Palato-pharyngeus. 



Relations. In the soft palate its posterior surface is covered by mucous 

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

 anterior surface it is in relation with the Tensor 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. 



In a dissection of the soft palate from its posterior or nasal surface to its anterior 

 or oral surface, the muscles would be exposed in the following order : viz. the 

 posterior fasciculus of the Palato-pharyngeus, covered over by the mucous membrane 

 reflected from the floor of the nasal fossse ; the Azygos uvulae ; the Levator palati ; 

 the anterior fasciculus of the Palato-pharyngeus ; the aponeurosis of the Tensor 

 palati. and the Palato-glossus covered over by a reflection from the oral mucous 

 membrane. 



Nerves. The Tensor palati is supplied by a branch from the otic ganglion ; 

 the remaining muscles of this group are in all probability supplied by the internal 

 branch of the spinal accessory, whose fibres are distributed along with certain 

 branches of the pneumogastric through the pharyngeal plexus. 1 



Actions. During the first stage of deglutition the morsel of food is driven back 

 into the fauces by the pressure of the tongue against the hard palate, the base of 

 the tongue being, at the same time, retracted, and the larynx raised with the 

 pharynx, and carried forward under it. During the second stage the epiglottis is 

 pressed over the superior aperture of the larynx, and the morsel glides past it ; 

 then the Palato-glossi muscles, the constrictors of the fauces, contract behind the 

 food ; the soft palate is slightly raised by the Levator palati. and made tense by 

 the Tensor palati ; and the Palato-pharyngei, by their contraction, pull the pharynx 

 upward over the morsel of food, and at the same time come nearly together, the 

 uvula filling up the slight interval between them. By these means the food is 

 prevented passing into the upper part of the pharynx or the posterior nares ; at 

 the same time the latter muscles form an inclined plane, directed obliquely down- 

 ward and backward, along the under surface of which the morsel descends into 

 the lower part of the pharynx. The Salpingo-pharyngeus raises the upper and 

 lateral part of the pharynx i. e. that part which is above the point where the 

 Stylo-pharyngeus is attached to the pharynx. 



Surgical Anatomy. The muscles of the soft palate should be carefully dissected, the rela- 

 tions they bear to the surrounding parts especially examined, and their action attentively studied 

 upon the dead subject, as the surgeon is required to divide one or more of these muscles in the 

 operation of staphylorraphy. Sir W. Fergusson was the first to show that in the congenital 

 deficiency called cleft palate the edges of the fissure are forcibly separated by the action of the 

 Levatores palati and Palato-pharyngei muscles, producing very considerable impediment to the 

 healing process after the performance of the operation for uniting their margins by adhesion ; he, 

 consequently, recommended the division of these muscles as one of the most important steps in 

 the operation. This he effected by an incision made with a curved knife introduced behind the 

 soft palate. The incision is to be halfway between the hamular process and Eustachian tube, 

 and perpendicular to a line drawn between them. This incision perfectly accomplishes the 

 division of the Levator palati. The Palato-pharyngeus may be divided by cutting across the 

 posterior pillar of the soft palate, just below the tonsil, with a pair of blunt-pointed curved 

 scissors : and the anterior pillar may be divided also. To divide the Levator palati the plan 

 recommended by Mr. Pollock is to be greatly preferred. The soft palate being put upon the 

 stretch, a double-edged knife is passed through it just on the inner side of the hamular process 



1 Journal of Anatomy and Physiology, vol. xxiii. p. 523. 



