president's address. 19 



association with a multitude of other processes, which we may 

 distinguish as absorptive, excretory, respiratory, metaboHc, &c., 

 and which, occurring as they do in such unison that the cell 

 develops and maintains itself, are characteristic of life." This he 

 justly points out to be a great advance on the idea that organic 

 growth was to be regarded as essentially similar to a process of 

 crystallisation. 



As regards the secretion and absorption of material by the 

 glands and intestine, it is shown that these cannot any longer be 

 regarded as due simply to filtration and diffusion, in that (1) the 

 secreting or absorbing surface is always composed of living cells; 

 (2) that the occurrence of secretion and apparently also of absorp- 

 tion involves processes of building up or growth, and breaking 

 down or waste of the cell substance, and is bound up with various 

 changes — respiratory, metabolic, electrical, &c., — which occur in 

 such unison that the secreting surface maintains itself; (-3) that 

 these processes are similar to those occurring in other cells. 



Again, in regard to respiration he points out (1) that oxidation 

 occurs within living cells ; (2) that its occurrence is intimately 

 associated with the various other characteristic evidences of vital 

 activity occurring in equally characteristic unison ; (3) that it 

 occurs in all the cells of the body. And, he continues — ''These 

 results not only imply the failure of particular theories of growth, 

 secretion, respiration, heat production, &c., but they entirely bear 

 out the vitalistic contention that the life of an organism in its 

 characteristic aspects can only be studied and understood as a 

 whole, and that attempts to analyse life into a mere series of 

 physical and chemical processes are based on a mistaken theory." 

 " It is evident from the illustrations just given that the physio- 

 logical comparison of cell with cell, or organism with organism, 

 has led to an enormously increased insight into life, so that in 

 this respect also the vitalistic theory has turned out to be an 

 excellent working hypothesis. But for misleading physico- 

 chemical theories the very fruitful method of comparing with one 

 another different forms of vital activity might have been adopted 



