98 THE GERM THEORY OF DISEASE. 



repetitions continue. But in this I am anticipating ; waste 

 products will be discussed in another lecture. 



CELLULAR DIGESTION IN THE HIGHER 

 ANIMALS. 



In the higher forms of life we find a division of labor in 

 the primary portions of the nutritive function, the prepara- 

 tion of the material for nutrition. Certain portions of the 

 animal body are set apart, so to speak, to perform this func- 

 tion for the whole. In the lower forms this function is 

 performed by the whole mass of cells as a unit, each doing a 

 part as an element of the mass. In proof of this we have 

 cited the instance of the bacterium, in blood, where digestion 

 can only be accomplished by the united efforts of a mass of 

 cells. We find, then, that in the lower forms of life cells 

 may act for each other in the matter of primary digestion, 

 and that in the higher forms of life a special development 

 occurs which enables certain cells to act for the general mass. 

 But in the matter of nutritive digestion each individual cell 

 must act for itself in the one case, as in the other. Here 

 there can, in the very nature of things, be no vicarious 

 function. 



Is it impossible that the cells of the higher animals may 

 excrete digestive fluids ; soluble ferments, also, under certain 

 particular circumstances? We shall see. 



RESORPTIVE DIGESTION. 



We now approach an important point in this discussion, 

 the third form, or resorptive digestion. 



We wish to state distinctly that all resorptiori and absorp- 

 tion of material not primarily fluid, that is, not simply en- 

 dosmotic, is of the same nature as primary digestion, and is 

 performed in a similar manner and by similar agencies, 



