672 



DISSECTION OF THE NOSE. 



Respiratory 

 region. 



Olfactory 

 region. 



the vestibule has the characters of the outer skin, being furnished 

 with papillae and hairs (vibrissae), and lined by a stratified scaly 

 epithelium. 



The respiratory region is the part below the level of the middle 

 turbinate bone. Its mucous membrane is thick, of a red colour, 

 very vascular, and has numerous mucous glands, the openings of 

 which are readily seen on the. surface. The glands are largest and 

 most abundant on the inferior turbinate bone, and'at the lower and 

 back part of the cavity. The epithelium of this region is columnar 

 and ciliated. 



The olfactory region is the narrowed upper part of the nasal fossa, 

 which is enclosed by the ethmoid bone. It comprises the part of the 



FIG. 238. NERVES OF THE SEPTUM OF THE NOSE. 



1. Olfactory bulb and inner set of 

 olfactory nerves. 



2. Nasal nerve of the ophthalmic 

 trunk. 



3. Naso - palatine nerve from 

 Meckel's ganglion (too large in the 

 figure). 



Mucous 

 membrane 

 in sinuses. 



roof formed by the cribriform plate, the part of the septum (about 

 one-third) formed by the perpendicular plate of the ethmoid, and, 

 on the outer wall, the upper and middle turbinate bones, together 

 with the flat surface of the lateral mass of the ethmoid in front of 

 the former. Over this region the olfactory nerves are distributed, 

 and it is, therefore, the seat of the sense of smell. The olfactory 

 mucous membrane i thinner, softer, and less vascular than that in 

 the respiratory region, and it has in the fresh state a yellowish 

 colour. Its epithelium is columnar, but not ciliated ; and it is 

 thickly beset with simple tubular glands. 



In the sinuses the mucous lining is thin and pale, and its glands 

 are few and small. 



