DIGESTIVE ORGANS STOMACH. 



523 



beneath the lining membrane; are probably concerned in the separa- 

 tion of some secretion from the blood, and when filled burst, like other 

 secreting cells, and discharge their contents into the stomach. 1 



The pylorus, or the part at which the stomach terminates in the 

 small intestine, isrnarked, 



externally, by a manifest Fig. 224. 



narrowness, as at 9, Fig. 

 219. Internally, the mu- 

 cous membrane forms a 

 circular fold, which has 

 been called valve of the 

 pylorus, between the two 

 laminae of which, a dense, 

 fibrous tissue exists. This 

 has been called by some 

 authors, pyloric muscle. 



The muscular coat, 

 which is exterior to the 

 mucous coat, as in the 

 parts of the digestive 

 tube already described, 



Consists of Several laminae Front View of Stomach, distended by flatus, with Peritoneal 



of fibres, less distinct than Coat turned off - 



fVinco rf fVio rAarvrvViQ rrnc 1. Anterior face of ossophagus. 2. Cul-de-sac, or greater ex - 



SOpnagUS, tremity 3. Lesser or pyloric extremity. 4. Duodenum. 5,5. 



Or rather more irregularly -^ portion of the peritoneal coat turned back. 6. A portion of 



-,. ., mu ^ e l on oit uc 'i na ' fibres of the muscular coat. 7. Circular fibres 



distributed. Hie mOSt of the muscular coat. 8. Oblique muscular fibres, or muscle of 



/ -krnmrvn /-vK>ir>irr ia -fliaf Gavard. 9. A portion of the muscular coat of the duodenum, 



Ib, Uld,L w here its peritoneal coat has been removed. 



there are three laminae: 



an external, longitudinal series ; a middle transverse or circular stratum ; 

 and an inner stratum with fibres running obliquely. Both circular and 

 longitudinal fibres are separated from each other, especially in the 

 splenic portion, the separation augmenting or diminishing with the 

 varying size of the stomach. 



The blood-vessels and nerves of the stomach are more numerous than 

 those of any other organ of the body. The arteries are disposed along 

 the curvatures. On the lesser curvatures are, coronaria ventriculi, 

 and the pyloric branch of the hepatic artery; on the great curvature, 

 the right gastro-epiploic, which is a branch of the hepatic; and the left 

 gastro-epiploic, a branch of the splenic. The splenic artery, too, 

 furnishes numerous branches to the left cul-de-sac behind. These are 

 called vasa brevia or Castro-splenic. The nerves of the stomach are of 

 two kinds. Some proceed from the great sympathetic, from the cceliac 

 plexus, and accompany the arteries through all their ramifications. 

 Others are furnished by the pneumogastric or eighth pair ; the two 

 nerves of which surround the cardiac orifice like a ring. The number 

 of the nerves, and the variety of sources whence they are derived, ex- 

 plain the great sympathetic influence exerted upon the stomach by 

 affections of other parts of the system. It sympathizes, indeed, with 



1 Kirkes and Paget, Manual of Physiology, Amer. edit., p. 167, Philad., 1849, 



