THE SENSES OF SMELL AND TASTE. 



SMELI.. 



The nose internally may be divided into a respiratory and 

 an olfactory region. The latter, -whicli corresponds, of course, 

 with the distribution of the olfactory nerve, embraces the upper 

 and part of the middle turbinated bone and the upper part of 

 the septum, all of which differ in microscopic structure from 

 the respiratory region. Among the ordinary cylindrical epi- 

 thelium of the olfactory region are found peculiar hair-cells 

 highly suggestive of those of the labyrinth of the ear, and 



Fio. 418.— Parts concerned in smell (after Hirschfeld). 1, olfactory ganglion and 

 nerves; 2, branch of nasal nerve, distributed over the turbinated bones. 



which are to be regarded as the end-organs of smell. If aromatic 

 bodies be held before the nose, and respiration suspended, they 

 will not be recognized as such, and it is well known that sniff- 



