OLFACTORY NERVE. 



137 



surface layer are strata of granules and ovalish cells ( 2 ), amongst which 

 sink the pointed or attached ends of the pieces of epithelium. 



Around the pieces of the columnar epithelium stand numerous bodies 

 named olfactorial cells by Sehultze (fig. 32 B. *). They consist of small 

 spindle-shaped nucleated cells, with a rounded filament prolonged from 

 each end towards the attached and free surfaces of the mucous membrane : 

 that to the free surface, the larger, ends on a level with the pieces of the 

 columnar epithelium. But the connections of the deeper threads or pro- 

 cesses are unknown ; they have been supposed to unite with the olfactory 

 nerve. 



The glands in the olfactory region are simple lengthened tubes (fig. 

 32 A. 4 ) like those in the stomach, but are slightly wavy, and end in the 

 submucous tissue by closed extremities. A flattened epithelium, with 

 colored granular contents, lines the tubes (Henle.) 



Dissection. At this stage of the dissection, little will be seen of the 

 distribution of the olfactory nerve. If the septum nasi be removed, so as 

 to leave entire the membrane covering it on the opposite side (the left), 

 the filaments of the nerve will appear on the surface, near the cribriform 

 plate. In the membrane, too, near the front of the septum, is an offset of 

 the nasal nerve. 



The naso-palatine nerve and artery (fig. 33, s ) are to be sought lower 

 down, as they are directed from behind forwards, towards the anterior 



Fig. 33. 



NERVES OP THE SEPTUM OP THE NOSE. 



1. Olfactory bulb and its ramifications on tbe 3. Naso-palatine nerve from Meckel's ganglion 



septum. (too lar^e in the cut.) 



2. Nasal nerve of the ophthalmic trunk. 



palatine fossa; the artery is readily seen, especially if it is injected, but 

 the fine nerve, which is about as large as a coarse hair, is imbedded in the 

 membrane and will be found by scraping with the point of the scalpel. 



By cutting through the fore and upper part of the membrane that has 

 been detached from the septum nasi, other branches of the olfactory nerve 

 may be traced on the outer wall of the nasal fossa. 



