I220 A MANUAL OF ANaTOMY 



canal the Vidian nerve gives off one or two nasal branches, which 

 pass through the floor of the canal, and are distributed to the 

 mucous membrane of the posterior part of the roof of the nasal fossa 

 and adjacent part of the septum. 



Branches of the Spheno-palatine Ganglion. — ^These are arranged 

 in four sets, and are as follows : 



Ascending Branches. — These are called the orbital branches. 



They are two or three in number, and enter the orbit through the 

 spheno -maxillary fissure, to be distributed to the periosteum. 

 They have been described by Luschka as sending filaments through 

 the inner wall of the orbit to supply the mucous membrane of the 

 posterior ethmoidal cells and the sphenoidal air-sinus. 



Posterior Branches. — ^These are the pharyngeal and the Vidian 

 nerves. The pharyngeal nerve passes backwards in the pterygo- 

 palatine canal, along with the pterygo-palatine artery, and is dis- 

 tributed to the mucous membrane of the upper part of the pharynx 

 in the region of the Eustachian orifice. 



The Vidian nerve (just described), if it is to be regarded as a 

 posterior branch of the ganglion, establishes a communication 

 between it and (i) the geniculate ganglion of the facial, through 

 means of the great superficial petrosal, and (2) the carotid plexus 

 of the sympathetic, through means of the great deep petrosal. 



Internal Branches. — ^These are the superior nasal and naso- 

 palatine nerves. The superior nasal nerves are of small size, and 

 derive some of their fibres from the spheno-palatine nerves. They 

 are about six in number, and, springing from the inner part of the 

 ganglion, they enter the superior meatus of the nose through the 

 spheno-palatine foramen. They supply the mucous membrane of 

 the superior and middle conchae, the superior meatus, the posterior 

 ethmoidal cells, the middle meatus, and the upper and back part 

 of the septum. 



The naso-palatine nerve {nerve of Cotunnius) enters the nasal 

 fossa along with the superior nasal nerves. It crosses the roof of 

 the fossa, and then passes downwards and forwards upon the septum, 

 lying in the groove on the lateral surface of the vomer. Having 

 arrived at the region of the incisor crest, the left naso-palatine nerve 

 descends through the anterior foramen or canal of Scarpa, and the 

 right descends through the posterior. Having reached the anterior 

 palatine fossa in this manner, the two nerves communicate in a 

 plexiform manner, and delicate filaments are furnished to the 

 mucous membrane of the hard palate behind the incisor teeth. In 

 this situation communications are established with the great or 

 anterior descending palatine nerve of each side. As the naso- 



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