506 SMALL INTESTINES. 



point of entrance of the oesophagus, and is embraced by the concave sur 

 face of the spleen. The pylorus is the small and contracted extremity of 

 the organ ; near its extremity is a small dilatation which was called by 

 Willis the antrum of the pylorus. The two curvatures give attachment to 

 the peritoneum ; the upper curve to the lesser omentum, and the lower to 

 the greater omentum. The anterior surface looks upwards arid forwards, 

 and is in relation with the diaphragm, (which separates it from the viscera 

 of the thorax and from the six lower ribs,) with the left lobe of the liver, 

 and in the epigastric region with the abdominal parietes. The posterior 

 surface looks downwards and backwards, and is in relation 'with the dia- 

 phragm, the pancreas, the third portion of the duodenum, the transverse 

 meso-colon, the left kidney, and left supra-renal capsule ; this surface 

 forms the anterior boundary of that cul-de-sac of the peritoneum w r hich is 

 situated behind the lesser omentum and extends into the greater omentum. 



SMALL INTESTINE. 



The small intestine is about twenty-five feet in length, and is divisible 

 into three portions, duo denum, jejunum , and ileum. 



The Duodenum (called <$Gj<5sxa<5a*<ruXov by Herophilus) is somewhat larger 

 than the rest of the small intestines, and has received its name from being 



Fig. 221. 



about equal in length to the breadth of twelve fingers. Commencing at 

 the pylorus, it ascends obliquely backwards to the under surface of the 

 liver ; it next descends perpendicularly in front of the right kidney, and 



A vertical and longitudinal section of the stomach and duodenum, made in such a 

 direction as to include the two orifices of the stomach. 1. The oesophagus ; vpon its 

 internal surface the plicated arrangement of the cuticular epithelium is shown. 2. The 

 cardiac orifice of the stomach, around which the fringed border of the cuticular epithe- 

 lium is seen. 3. The great end of the stomach. 4. Its lesser or pyloric end. 5. The 

 lesser curve. 6. The greater curve. 7. The dilatation at the lesser end of the stomach, 

 which has received from Willis the name of antrum of the pylorus. This may be re- 

 garded as the rudiment of a second stomach. 8. The rugae of the stomach, formed by 

 he MUCOUS membrane : their longitudinal direction is shown. 9. The pylorus. 10. 

 The oblique portion of the duodenum. 11. The descending portion. 12. The pancreatic 

 duct and the ductus communis choledochus close to their termination. 13. The papilla 

 upon which the ducts open. 14. The transverse portion of the duodenum. 15. The 

 commencement of the jejunum. In the interior.of the duodenum and jejunum the vaJ- 

 v ulae conniventes are seen 



