IT).; Proceedings of the Ohio State Academy of Science 



into the cell substance directly. The body cells of the higher 

 forms are specialized and cannot digest food for themselves. 

 They are suspended in the body fluid, the lymph, in exactly 

 the same sense as the amoeba, the difference being that these 

 cells can not go after their food like the amoeba which may 

 move about in the water from poorer to richer feeding- 

 grounds, but their food must be piepaied and brought to them 

 by the circulation of the f^uid in which they are suspended. 

 The blood ciiculates in a closed system of vessels and doe^ 

 not bathe the cells in general, but the lymph or body fluid has 

 its origin mainly in tlie blood by dializing through the walls 

 of the capillaries and bathes the cells of the body. The cir- 

 culating media of the body carry on a double function. The 

 distributing of the food has already been mentioned but the 

 other side, the carrying the waste from the cells is as neces- 

 sary to the life of the body as the food supply. Activity means 

 waste in everv place so every living organism is constantl}' 

 producing matter that must be eliminated. The cells can not 

 get away from i'; therefore it must be carried from the cells. 

 If the cells can not get the food necessary and can not get 

 rid of the waste matter, first they will starve and secondly 

 they will be choked and death will be the result in either case. 

 The body as a whole is alive or dead in proportion to the 

 number of cells that are living or dead. The main point here 

 is the absolute necessity f(ir a circulatory medium and that 

 this medium be kept in motion ma'nly en account of the s]ie- 

 cialized conditicm and the size (jf the human body. Small 

 l)odies like the amoeba can come in contact on all sides with 

 the food, but with large l)()dies it is n(^t so. To satisfy these 

 conditions the blood must be put under pressure in the ar- 

 teries. This pressure must be kept up and the arteries fiill 

 of blood all the time. These conditions being mantained the 

 blood will circulate to the points of least resistance. The re- 

 sistance will denend upon the activity of the organ or organs 

 in question. This will inclu'le muscular activity, glandular 

 activity, etc. Anv activity will force the blood out of an or- 



