BLOOD AND LYMPH. 



101 



Lymph 



Capillary. 



Lymph is a clear liquid. (Chyle and the lacteals will be 

 considered when we study digestion.) It is more watery than 

 the blood plasma, but contains a share of all its nutritious 

 substances. Lymph may. be denned as diluted blood minus 

 red corpuscles. The blood proper never reaches the tissues. 

 The cells of the tissues are bathed in the lymph which fills 

 the spaces in the connective tissue (and we have seen that the 

 connective tissue pervades nearly all the tissues of the body), 



as water may fill the spaces 

 left between stones built in- 

 to a wall. The cells get all 

 their nourishment from the 

 lymph, and into the lymph 

 they throw all their waste 

 matter. Each cell may be 

 compared to an individual 

 ameba, which lives in water, 

 and takes all its nourish- 

 ment from that water, and 

 throws all its waste product 

 into the same water. As 

 water is the medium ir 

 which the ameba lives, so 

 we may say lymph is the 

 medium in which the cells 

 of the body live. 



The cells of the body, 

 i.e., all the active, working 



cells, may, therefore, be said to live an aquatic life, and only 

 dead cells, as of hair, epidermis, etc., are in air. We might 

 also say that not only the human body, but all animal life, 

 is aquatic. 



We can see that the movement and renewal of the lymph 



Oxygen - 



Food 



Other 

 Wastes 



Fig. 38. Relation of Blood and Muscle. 

 (Lymph being middleman.) 



