88 EVOLUTION OF THE EARTH 



Obviously, then, the biologist in dealing with living sub- 

 stance has it only in the form of cells, and these, singly or col- 

 lectively, constitute individual organisms. Thus in the final 

 analysis protoplasm is known to us only in the form of living 

 individuals, and the expressions "protoplasm" and "life" are 

 merely abstractions, one indicating that all individuals have 

 to a certain extent a common organizational foundation and 

 the other that they exhibit certain characteristic actions and 

 reactions. The living organism is a microcosm which exhibits 

 a permanence and continuity of individuality correlated with 

 specific behavior, and this it transmits to other matter which 

 it makes a part of itself and to its offspring in reproduction. 



It is apparent that the phenomena which we call life are 

 dependent upon the interplay and interchange between the 

 highly organized protoplasmic complex and its environment. 

 Although the organism, whether animal or plant, is an indi- 

 vidual, still it retains its individuality lives solely by its 

 powers of developing and maintaining exquisite adjustments to 

 its surroundings, and therefore the concept protoplasm has 

 little or no content unless environmental relations are included. 

 This fitness of the organism, as Henderson has recently empha- 

 sized, is but one part of a reciprocal relationship of which 

 the fitness of the environment is the other. "The fitness of the 

 environment results from characteristics which constitute a 

 series of maxima unique or nearly unique properties of 

 water, carbonic acid, the compounds of carbon, hydrogen, 

 and oxygen and [for primordial life] the ocean." "No other 

 environment consisting of primary constituents made up of 

 other known elements, or lacking water and carbonic acid, 

 could possess a like number of fit characteristics" for proto- 

 plasmic phenomena. The properties of matter and the course 

 of cosmic evolution are intimately related to the structure of 

 the living being and to its activities. Indeed, "the whole evolu- 

 tionary process, both cosmic and organic, is one, and the biolo- 



