288 



ABSORPTION 



into the thoracic duct, and the latter communicates 

 with the left subclavian vein, and thus returns the 

 excess of lymph back to the blood-stream. 



The wonderful aspect of absorption is the apparently 

 unsolvable problem in regard to how these numbers 

 of cells in the villi of the intestinal mucous membrane 



FIQ. 107 



PLANE OF MU- 

 COUS SURFACE 



Mucosa of small intestine in ideal vertical cross-section. (Testut, after 

 Heitzmann.) 



can absorb the different constituents of the nutritive 

 materials from the alimentary canal and transfer 

 them into the lymph spaces to be absorbed by the 

 blood capillaries and lymphatics. 



It is supposed to be due to a "selective action" 

 based on their organization and living condition, an 

 fiction which is to a great extent conditioned and 



