88 ELEMENTARY BIOLOGY. [CHAP. 



i. The hepatic portal vein will now be seen emerging 

 from the head of the pancreas to enter the left 

 lobe of the liver (cf. § 3); it is formed by the 

 union of the following factors. 



a. The gastric vein ; bringing back the blood from 

 the stomach. 



b. The superior mesenteric vein ; a very short vessel 

 running through the head of the pancreas and 

 receiving 



a. The duodenal veins; bringing in the blood 

 from the duodenum and pancreas. 



/?. The lieno-intestinal vein; formed by the union 

 of the ileal from the ileum, the hemorrhoidal 

 from the large intestine, and the splenic or 

 lienal from the spleen. 



ii. The casliaco-mesenieric artery may now be traced to 

 its ultimate distribution. Its origin has been 

 described at § 9 a; it breaks up near the head of 

 the pancreas into a and b. 



a. The cceliac artery; distributing branches to the 

 stomach, liver and pancreas, 



b. The superior mesenteric artery; supplying the 

 intestine and spleen. The branches of- this 

 vessel accompany the factors of the superior 

 mesenteric vein. 



c. The inferior mesenteric artery ; arising from the 

 dorsal aorta far back and supplying the base of 

 the large intestine (cf. § 9 d). 



iii. Remove the hinder half of the hip-girdle and the 

 head of the femur. Scrape away the liver to the 



