GREAT VESSELS AND NERVES OF NECK 311 



Even then the dissection is a difficult one, although it should certainly be 

 undertaken by the advanced student, in the event of his being able to obtain 

 a part for the purpose. 



In the following description of these nerves the account 

 of the branches which can in all cases be traced is printed in 

 ordinary type, whilst that of those requiring special dissection 

 is printed in small type. 



Nervus G-losso-pharyngeus. The glosso-pharyngeal nerve 

 inclines downwards and anteriorly and crosses the internal 

 carotid artery superficially. At first it lies medial to the 

 styloid process and the stylo - pharyngeus muscle, then it 

 hooks round the lower border of the muscle and curves 

 anteriorly upon its superficial surface to gain the base of 

 the tongue. In the dissection of the submaxillary region, 

 its terminal part was seen disappearing under cover of the 

 hyoglossus muscle, where it ends in lingual branches. 



In the present dissection the following branches should be 

 made out : 



1. Communicating branch from 



the facial. 



2. Nerve to the stylo-pharyngeus. 



3. Pharyngeal. 



4. Tonsillitic. 



5. Lingual. 



The communicating branch from the facial springs from the nerve to 

 the posterior belly of the digastric, and, as a rule, emerges from midst the 

 fibres of that muscle to join the glosso-pharyngeal close to the lower part of 

 the jugular foramen. 



The stylo-pharyngeal nerve is a small twig which enters the 

 muscle of the same name. The greater part of its fibres, 

 however, are continued through the muscle to the mucous 

 membrane of the pharynx. 



The pharyngeal branches consist (i) of one or two small 

 twigs which perforate the superior constrictor to reach the 

 mucous membrane of the pharynx ; and (2) a larger nerve 

 which comes off higher up and passes with the pharyngeal 

 branch of the vagus to the pharyngeal plexus. It frequently 

 divides into two or more branches. 



The tonsillitic branches proceed from the glosso-pharyngeal 

 near the base of the tongue. They form a plexus over the 

 tonsil, termed the drculus tonsillaris, and give twigs to the 

 mucous membrane of the isthmus faucium and the soft 

 palate. 



The terminal or lingual branches will be followed in the 

 dissection of the tongue. 



ii 20 c 



