ANALYSIS OF CELL ACTIVITIES 85 



in England (1895), and best summed up by a modification of 

 the aphorism of the botanist De Bary quoted by D'Arcy Thomp- 

 son : " It is the individual that forms cells, not cells that form 

 the individual." This is diametrically opposed to the teaching 

 of Virchow in his Cellular "paihologie that " Every animal appears 

 as a collection of vital units, each of which bears in itself the 

 full character of Life." 



In either case, whether in the unicellular or in the multi- 

 cellular organism, the individual continues to grow and exhibit 

 predominantly vegetative activities until it reaches this limit 

 of economical relationship between itself and its environment. 

 In the very earliest stages the vegetative activities alone are 

 evident : as the above-mentioned limit is approached these 

 become less and less, and the cells are more and more engaged 

 in functional activities, that is to say, they utilize the food-stuffs 

 received, not in building up more living matter, but for the 

 performance of work and liberation of energy. And to the 

 extent that growth necessitates a building-up process from the 

 food-stuffs presented to the cell, and function necessitates a 

 breaking down and burning up 1 of the same food-stuffs, to this 

 extent the vegetative or — as Weigert terms them — bioplastic, 

 and the functional, or katabiotic, activities are opposed processes. 



(iii.) Metabolism. — It may be thought that in mentioning 

 these matters I am wandering far afield, and through a singularly 

 arid field at that, nay more, that I do but touch upon or outline 

 matters which to be grasped in all their bearings need a much 

 fuller presentation. I touch upon them purposely in order to 

 emphasize that these matters of adaptation and evolution have 

 of necessity to be approached from the aspect of function and the 

 dynamics of living matter, rather than from the point of view of 

 cell statics. " Function," it has been said, " precedes structure," 

 and it is the study of cell function that must afford the key. 



If next we proceed to enquire into the state of our knowledge 

 of the chemistry of these active processes occurring within the 

 cell, we reach a further stage, for the more we study the processes 

 of absorption of food and utilization of the same — the metabolic 

 processes whether, as Gaskell termed them, of anabolism, building 



1 It is not (as one is apt to imagine) the dissociation of the food-stuffs that 

 liberates energy, but the burning up of the same, i.e. the oxidation of the 

 dissociated food-stuffs. 



