280 



STUDIES IN ADVANCED PHYSIOLOGY. 



outer muscle fibres run longitudinally. The middle coat is 

 circular, but inside of the middle coat there is a third coat 

 not quite complete, in which the direction of the fibres is 

 oblique. This especial development of the muscles is no 

 doubt intended to make possible the movements of the 

 stomach which accompany gastric digestion. 



The sub-mucous coat binds down to the muscular coat 

 the large glandular mucous coat of the stomach. This 

 mucous coat is covered on the inside with a single-lavered 



Fig. 110. A CARDIAC GLAND FROM THE Fig. 111. A GASTRIC GLAND STAINED BY 



DOG'S STOMACH. (After Klein and No- 

 ble Smith.) 



d, duct of gland; b, base or fundus; c, 

 ordinary peptic cell; p t oxyntic cell. 



CHROMATE OF SILVER, SHOWING THE 

 EXTENSION OF THE LUMEN INTO THE 

 NETWORKS SURROUNDING THE OXYN- 

 TIC CELLS, FOR THE EXIT OF THK ACID 

 SECRETION OF THESE CELLS. (After 



Miiller.) 



epithelium, which everywhere dips down into the mucous 

 coat and forms pits, or more properly speaking, tubular 

 glands. These glands are the gastric glands. The epi- 

 thelial lining of the inside of the stomach is continued into 



