312 SUPERIOR MESENTERIC ARTERY. 



culates with the gastro-epiploica dextra. It is distributed to the gre 

 curve of the stomach and to the great omentum. 



Fig. 153. 



The SUPERIOR MESENTERIC ARTERY, the second of the single trunks, 

 and next in size to the cceliac axis, arises from the aorta immediately below 

 that vessel, and behind the pancreas. It passes forwards between the 

 pancreas and transverse duodenum, and descends within the layers of the 

 mesentery, to the right iliac fossa, where it terminates, very much dimi- 

 nished in size. It forms a curve in its course, the convexity being directed 

 towards the left, and the concavity to the right. It is in relation near its 

 commencement with the portal vein ; and is accompanied by two veins, 

 and the superior mesenteric plexus of nerves. 



The branches of the superior mesenteric artery are 



Vasa intestini tenuis, 

 Ileo-colica, 

 Colica dextra, 

 Colica media. 



The Vasa intestini tenuis arise from the convexity of the superior me- 

 senteric artery. They vary from fifteen to twenty in number, and are dis- 



* The distribution of the branches of the cceliac axis. 1. The liver. 2. Its transverse 

 fissure. 3. The gall-bladder. 4. The stomach. 5. The entrance of the oesophagus. 

 6. The pylorus. 7. The duodenum, its descending portion. 8. The transverse portion 

 of the duodenum. 9. The pancreas. 10. The spleen. 11. The aorta. 12. The co3liac 

 axis. 13. The gastric artery. 14. The hepatic artery. 15. Its pyloric branch. 16. The 

 gastro-duodenalis. 17. The gastro-epiploica dextra. 18. The pancreatico-duodenalis, 

 inosculating with a branch from the superior mesenteric artery. 19. The division of 

 the hepatic artery into its right and left branches ; the right giving off the cystic branch. 

 20. The splenic artery, traced by dotted lines behind the stomach to the spleen. 21. 

 The gastro-epiploica sinistra, inosculating along the great curvature of the stomach with 

 the gastro-epiploica dextra. 22. The pancreatica magna. 23. The vasa brevia to the 

 great end of the stomach, inosculating with branches of the gastric artery. 24. The 

 superior mesentpric artery, emerging from between the pancreas and transverse portiod 

 f the duodenum. 



