44 BIOLOGY OF THE PROTOZOA 



A starving DUeidus an.ser will slowly decrease in size although its 

 form remains abont the same. This is due to disintegration through 

 continued oxidation and other catalytic processes which lead to the 

 exhaustion of protoplasmic constituents unless new food is added. 

 If the ])rocess is continued the organism will ultimately die in from 

 one to three weeks. If a DUeptus is accidentall\' crushed its proto- 

 plasm will completely disintegrate within a few seconds. The 

 process of disintegration in the first case is orderly, in the latter 

 completely disorganized. Other normal vital activities are equally 

 orderly; the orderliness dependent possibly on the regulation of 

 permeability by the colloidal membranes, the alveolar membranes, 

 nuclear membrane and investing membrane of the cell; and regula- 

 tion of permeability in turn is dependent upon the chemical make-up 

 of the constituent parts, and the salts or electrolytes and the con- 

 tinued activity between them (Cf. Clowes, Overton, Mathews). 



The speed of specific chemical actions is a characteristic vital 

 phenomenon due to the participation of subtle and elusive, but 

 specific, catalytic agents, the enzymes. 



This aggregate of colloidal substances forming poly{)hasic physical 

 systems in protoplasm is the seat of the multitude of activities 

 characteristic of life. Huxley's definition of protoplasm as the 

 physical Basis of Life does not carry us very far in the analysis of 

 living matter. Indeed it may well be that the physical basis of 

 protoplasm is itself life (see Chapter IV) and that protoplasm in the 

 words of du Bois Reymond, is the agent of vital manifestations. 

 In a moving protozoon there is a constant interaction of the various 

 substances making up its protoplasm— oxidation, enzyme formation 

 and action, amidization and deamidization, disintegration and 

 regeneration, protein break-down and protein reconstruction, all 

 taking place simultaneousl.y or seriatim. Substances in this w^hirl- 

 pool of action may be regarded as living so long as they are, or may 

 be, drawn into the vortex of protoplasmic activities. The results 

 of these multitudinous activities contribute to the well-being of 

 one organism. In another moving protozoon a similar bewildering 

 complex of activities likewise results hi the well-being, in this case 

 of a distinctly different ty^e of protozoon. The first protozoon, 

 let it be a Didiniimi nasnhtm, captures and swallows the second, 

 say a Paramecium cavdatum. It is well known that a fragment of 

 a protozoon will regenerate into a perfect organism of its type 

 and we might well be perplexed b\' the problem why is it that the 

 Paramecium protoplasm in Didinium does not manifest itself as 

 Paramecium and not as Didinium. The answer to this apparently 

 simple problem is possibly a matter of organization or the manner 

 in which the fundamental substances making up the protoplasm in 

 the two organisms are put together and interact. The architeck- 

 tonic of Driesch, or protoplasmic architecture is specific for each 



