THE PHARYNX. 



315 



FIG. 92. 



riorly to the fourth, or fifth cervical vertebra behind the 

 lower part of the cricoid cartilage, where it ends in the 

 ossophagus. 



Dissection. Make a transverse incision at the lower part 

 of the neck, through the trachea and oesophagus; turn 

 these up with the vessels and nerves, to the base of the 

 cranium, and then detach the head from the spine, by 

 disarticulating at the atlas, or, 

 which is more convenient, by 

 sawing between the atlas and 

 dentata now stuff the pharynx 

 with curled hair, or tow, or cot- 

 ton, and it is prepared for dis- 

 playing its muscles. The pha- 

 rynx is a musculo-membranous 

 sac or cavity, somewhat of an 

 oval form, attached superiorly to 

 the cuneiform process of the oc- 

 cipital bone, by a strong apon- 

 eurosis; posteriorly, to the deep 

 muscles of the neck and cervi- 

 cal vertebrae, by a loose cellular tissue; anteriorly, to the 

 internal pterygoid plate of the sphenoid bone, hamular 

 process, posterior part of the upper jaw, and mylo-hyoid 

 ridge of the lower jaw also to the sides of the tongue, the 

 cornua of the os-hyoides, and the sides of the cricoid and 

 thyroid cartilages. There is, besides, a lateral connection 

 with the petrous bone. By these several connections 

 the pharynx is kept constantly open, and its walls pre- 

 vented from falling together. 



Structure. The pharynx consists pf three coats, i. e. an 

 outer or muscular, a middle or cellular, and an inner or 

 mucous in addition to which, it abounds in blood-vessels 

 and nerves. 



FIG. 92 represents a view of the Constrictors of the Pharynx, and an ante- 

 rior view of the Palate. 1 1 Superior constrictor of the pharynx. 2 2 Mid- 

 dle constrictor. 3 3 Inferior constrictor. 4 4 Levator palati. 5 Uvula. 6 6 

 Anterior half arch. 7 Circumflexus, or tensor palati muscle. 



