148 



THE ESSENTIALS OF HISTOLOGY 



medullated nerve-fibres known as the plexus myentericus of Auerbacli. 

 The ganglia of this plexus may usually be seen in vertical sections of 

 the intestinal wall, but the plexus, like the one in the submucous coat 

 immediately to be described, can only be properly displayed in prepara- 

 tions made with chloride of gold (fig. 178). 



The submucous coat is like that of the stomach ; in it the blood- 

 vessels and lymphatics ramify before entering or after leaving the 

 mucous membrane, and it contains a gangliated plexus of nerve-fibres 



FIG. 179. PLEXUS OF MEISSNER FROM THE SUBMUCOUS COAT OF THE INTESTINE. 



(Cadiat.) 



the plexus of Meissner which is finer than that of Auerbach and has 

 fewer ganglion -cells (fig. 179). Its branches are chiefly supplied to the 

 muscular fibres of the mucous membrane. 



The mucous membrane is bounded next to the submucous coat by 

 a double layer of plain muscular fibres (muscularis mucosa). Bundles 

 from this pass inwards through the membrane towards its inner sur- 

 face and penetrate also into the villi. The mucous membrane proper 

 is pervaded with simple tubular glands the crypts of Lieberkiihn 

 which are lined throughout by a columnar epithelium like that which 

 covers the surface and the villi. The mucous membrane between these 



