THE ORGANS OF THE SPECIAL SENSES. 



Fig. 254. 



Ill 



271 



Epithelial layer of the human olfactory mucous membrane. (Brunn.) Isolated elements. 

 Three epithelial cells, with forked proximal ends, are represented, together with a ner- 

 vous cell bent out of position and the distal end of a second nervous cell. M.l, cuticle 

 of the columnar epithelium, which is not continued over the end of the nervous cell. 

 The cuticle of neighboring cells unites at the edges to form a species of membrane, which 

 appears to be perforated for the exit of the distal ends of the nervous cells. A similar 

 cuticle is found in the retina, where it has received the name " limiting membrane." 



Fig. 255. 



Vertical section of the epithelium, showing the arrangements of its elements. The nervous 



cells, with their neurites, are black. 



they terminate in teleneurites within little globular structures, called 

 the "glomeruli of the bulb." 



