ABSORPTION. 



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enters the liver at the transverse fissure, after which it forms a 

 fine capillary plexus ramifying throughout the substance of the 

 liver ; from this plexus the hepatic veins take their origin, and 

 finally empty the blood into the vena cava inferior. (See Fig. 16.) 



FIG. 1 6. 



Diagram of the portal vein (pv) arising in the alimentary tract and spleen (s), 

 and carrying the blood from these organs to the liver. (Yeo's "Text- 

 book of Physiology.") 



Absorption of Food. Physiological experiments have demonstrated 

 that the agents concerned in the absorption of new materials from 

 the alimentary canal are : 



1. The blood-vessels of the entire canal, but more particularly those 

 uniting to form the portal vein. 



2. The lymph vessels coming from the small intestine, which converge 

 to empty into the thoracic duct. 



As a result of the action of the digestive fluids upon the different 



