PHYSIOLOGICAL ANATOMY OF THE STOMACH 



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fibres extending over the great pouch only, which is internal to the 

 circular layer. The longitudinal fibres are continued from the oesopha- 

 gus and are most marked over the lesser curvature. They are not con- 

 tinued very distinctly over the rest of the stomach. The circular and 

 oblique fibres are best seen with the organ everted and the mucous 

 membrane removed. The circular layer is not very distinct to the left 

 of the cardiac opening, over the great pouch. Toward the pylorus, the 

 layers of fibres are thicker, and at the opening into the duodenum, they 

 form a powerful muscular ring, sometimes called the sphincter of the 

 pylorus, or the pyloric muscle. At this point they project considerably 



Fig. 37. Fibres seen -with the stomach everted (Sappey). 



i, i, oesophagus; 2, circular fibres at the oesophageal opening; 3, 3, circular fibres at the lesser 

 curvature ; 4, 4, circular fibres at the pylorus ; 5, 5, 6, 7, 8, oblique fibres ; 9, 10, fibres of this layer 

 covering the greater pouch ; n, portion of the stomach from which these fibres have been removed to 

 show the subjacent circular fibres. 



into the interior of the organ and cease abruptly at the opening into the 

 duodenum, so as to form a sort of valve, presenting, when contracted, a 

 flat surface looking toward the intestine. The oblique layer takes the 

 place, in great part, of the circular fibres over the great pouch. It 

 extends obliquely over the fundus from left to right and ceases at a 

 distinct line extending from the left margin of the oesophagus to about 

 the junction of the middle with the last third of the great curvature. 

 At about the line where the oblique layer of fibres ceases, the stomach 

 becomes constricted during the movements incident to digestion, divid- 

 ing the organ into two tolerably distinct compartments. The pyloric 

 division has lately been called the antrum pylori; and the rather 



