782 



A MANUAL OF ANATOMY 



or circular fibres completely surround the stomach from the 

 fundus to the pyloric end. At first they are thin and irregular in 

 position, but over the pyloric canal they are thick. At the pylorus 

 they become augmented, and are gathered together into a thick 

 muscular ring, called the sphincter pylori, which lies within a circular 

 fold of the mucous membrane. The outermost fibres of this ring 

 become continuous with the circular fibres of the duodenum. Some 

 of the circular fibres appear to be continuous with the superficial 

 circular fibres of the right side of the lower end of the oesophagus. 

 The internal or oblique fibres are continuous with the circular fibres 

 of the left side of the lower end of the oesophagus. They loop over 

 the stomach immediately to the left of the cardia, and run very 



Cardiac Orifice 



CEsophagus 



Fundus 



Small Curvature 

 Hepatic Duct^ 



Cystic Duct 

 Pylorus 



Ductus Communis - 

 Choledochus 



Great Curvature 



Duct of Wirsung 



Duodenum 



Fig. 334. — The Stomach and Duodenum opened. 



obliquely downwards and to the right for a considerable distance 

 on both surfaces of the organ . They cannot be traced as far as the 

 pylorus, but end by inclining downwards to the great curvature, 

 where they blend with the circular fibres. 



The submucous coat is situated between the muscular and 

 mucous coats. It is composed of loose areolar tissue, and serves 

 partly as a connecting medium, and partly as a bed in which the 

 arteries subdivide before entering the mucous coat. 



The mucous coat is covered by a single layer of columnar epi- 

 thelium, many of the cells being mucus-secreting goblet cells. It 

 is solt and pulpy, and in the empty state of the viscus is thrown into 

 rugae, which are for the most part longitudinal, and are due to the* 

 loose connection between the muscular and mucous coats. These,! 

 however, are readily effaced when the stomach becomes distended.! 



