1626 



HUMAN ANATOMY. 



important. This layer is composed of circular fibres, which are thickest and most 

 simply arranged near the pylorus. Owing to the enlargement of the upper end of 

 the stomach, and the fact that the cardiac opening is not at the end but at the side, 

 the arrangement becomes complicated. The fibres surround the cardia, but become 

 oblique at a short distance from it. At the top of the fundus they are arranged in a 

 whorl mingling with those of the internal layer. Still lower, although in the main 

 circular, their course is uncertain. Towards the pylorus they thicken considerably, 

 being particularly well dev^eloped in stomachs of which the pyloric part is tubular. 

 At the opening they are collected into a ring — xh^ pyloric sphincter — capable of closing 

 the orifice. The longitudinal layer is outside of the circular one and continuous 



Fig. 1378. 



Mouth of 



Fundus of gland 



Lymph-node. 





Muscularis mucosae 



Section of pyloric end of stomach, showing glands and part of lymph-node. • 100. 



with the longitudinal fibres of the oesophagus. Along the lesser curvature, and to a 

 less extent along the greater, these fibres are collected into bands ; over the front 

 and the back of the stomach they are oblique. At the antrum pylori, although the 

 layer is continuous all around, it presents an anterior and a posterior band, — the 

 Pyloric ligamoits, — that pass over folds of all the layers internal to them, thus 

 forming the duplicature at the beginning of the antrum. At the pylorus itself the 

 longitudinal layer, which has become thicker, sends a series of fibres through the 

 circular fibres, subdividing them into many groups, (Fig. 1391). The innermost 

 muscular layer consists of oblique fibres spreading out from the cardia o\'er the 

 front and back of the stomach. They are continuations of the circular fibres of 



