552 THE INTESTINAL CANAL. BY E. KLEIN AND E. VERSON. 



both on the surface and in the tubes themselves, in prepara- 

 tions hardened in chromic acid, is almost entirely composed of 

 cup cells. 



The muscularis mucosse in the cardiac portion consists for 

 the most part of longitudinal fasciculi, becoming somewhat 

 stronger towards and in the fundus, and exhibiting here at 

 most points a circular and longitudinal layer of equal thick- 

 ness. In the pyloric portion of the stomach the fasciculi of 

 both layers completely decussate with one another, and it is 

 only at certain points that a distinct circular and longitudinal 

 layer can be distinguished. Numerous fasciculi here branch 

 off into the mucosa. 



At the pylorus itself the muscularis mucosse, and especially 

 its longitudinal layer, increases five-fold in thickness. The 

 submucous tissue, which is here, as usual, continuous with the 

 septa of the external and internal muscular coat that dip into 

 the mucosa in company with numerous vessels, is thinner in 

 the pyloric region than at the fundus, and contains in its 

 small meshes numerous spheroidal cells with a relatively 

 large nucleus. 



The external musculature consists exclusively, as in man, 

 of smooth muscular fibres, and exhibits the following arrange- 

 ment : The circular layer is particularly strongly developed 

 at the cardia, but gradually diminishes towards the fundus. 

 The most external fasciculi of the longitudinal muscular layer 

 of the cardia are intimately connected with the fibres of the 

 investing membrane, pursue an oblique direction, and farther 

 down enter the circular muscular layer. 



In the pyloric region the relations are altered, and the 

 several layers have not only increased in thickness, but the 

 innermost fasciculi of the circular layer become for a short 

 distance oblique or longitudinal. 



At the pylorus itself the muscularis externa presents the 

 same arrangement as in the stomach of the dog, 



The nerves and ganglia lying between the two layers of the 

 muscularis externa form in parts a continuous layer, and in 

 parts are sparingly distributed. Ganglia are not very fre- 

 quently met with in the submucous tissue. 



The stomach of the RAT presents remarkable peculiarities of 



