896 



OBGANS OF SPECIAL SESSE 



The nerves. — The olfactory or special nerves of smell, the filaments of 

 which pas^s through the foramina in the criljriform plate of the ethmoid bone, lie 

 for some distance in the grooves of the bony walls before terminating in the 

 Schneiderian membrane. 



Those which supply the septum ramify in its upper fifth, whilst those which 

 reach the outer Avails are distributed in two groups — a posterior, to sui)ply the 

 membrane covering the superior turbinal bone, and an anterior, to ramify in the 

 membrane over the middle turbinal bone and the smooth surface of the ethmoid 

 in front of this. 



In addition to the special nerves of smell, the cavity is supplied Avith nerves of 

 common sensation derived from the fifth pair. 



The nasal branch of the ophthalmic supplies the front and upper part of the 

 septum, the anterior part of the roof and also the anterior part of outer Avail of 

 the nasal fossa. 



The Vidian, Avith the upper nasal branches of Meckel's ganglion, supply 



FRONTAL SINUS 



Fig. 520. — Nera'es of the Nasal Caa'ity. 



na sa l olfa ctor 1 " 

 xeh ve ner ve 



OLFA CTOR Y NER VE 

 TO SUPERIOR TUR- 

 BINA TE BONE 



SPHENOIDAL SINUS 



VIDIAN NERVE 



MECKEL'S 

 \ GANGLION 



^7— DESCENDING 

 PALATINE 



ORIFICE OF EUSTACHIAN 

 TUBE 



NASAL BRANCHES 



POSTERIOR 



PALATINE 

 ANTERIOR 



PALATINE 

 MIDDLE PA LA TINE 



the upper and back portion of the septum, the roof, and the4)Uter Avail, including 

 the superior spongy bone. 



The naso-palatine supplies the lower and posterior portion of the septum. 



The anterior dental branch of the maxillary division of the fifth nerve is 

 distributed to the anterior pai't of the inferior meatus and inferior turl)inal bone. 



The anterior or large palatine nerve supplies in its course downwards the 

 posterior })art of tlie middle and Ljwer turbinal liones. 



The arteries are distributed asfolloAvs: — 



Tlie spheno-palatine, from the internal maxillary by its internal or naso- 

 palatine branch, supi)lies the septum as it courses doAVUAvards and forwards in 

 the groove on the vomer to the incisor foramen. Its external branches su]iply 

 the antrum (also supplied by the alveolar branch of the facial) and frontal sinus, 

 the ethmoidal cells, and inner surfaces of the turbinal bones with tlic meatuses. 

 It enters the cavity through the si^heno-palatine foramen. 



