INTRODUCTION 45 



type of organism and the form and structures of the organism are 

 expressions of this architecture which is as perfect in a spherical 

 fragment of a Stenfor or of a Dikptus as it is in the fully developed 

 Stentor or Dileytus. When this organization disintegrates, life and 

 the possibility of controlled reactions are lost and the erstwhile 

 living protoplasm becomes dead matter. This happens when 

 Paramecium is paralyzed by the seizing organ of Didinium (see 

 Fig. 89, p. 180). The vital activities of Paramecium are suddenly 

 stopped, and disintegration of the protoplasmic organization of 

 Parameciwn continues with the process of digestion in Didinium. 

 Then the inert proteins, probably as amino-acids, are reintegrated 

 in the Didinium protoplasm and what was living substance in Par- 

 amecium now enters again, through a form of transmigration, into 

 the vortex of vital activities of quite another type of organism. 



Consideration of these and of similar activities in living proto- 

 plasm lead to questions regarding the nature of life and the nature of 

 vitality. Should we use the two terms life and vitality as synonyms ? 

 It seems that there is something to be gained by distinguishing 

 between them. We are very apt to speak of life as actiA'ity, or to 

 say that life is a series of reactions, integrations and disintegrations. 

 These may be manifestations of life but they are incomplete mani- 

 festations and do not tell the whole story. An encysted protozoon, 

 a spore, a seed, a resting egg, or a dried rotifer, show no evidence of 

 activity, yet each has life and in a proper environment would mani- 

 fest activity. An emulsion of oil, salts and water, manifests activ- 

 ity strikingly similar to the movements of an Amoeba yet such an 

 emulsion has no life. The encysted protozoon or the dried rotifer 

 has protoplasmic organization which the oil emulsion has not, and 

 with absorption of oxygen and water becomes animated. Life 

 thus is incontestably bound up with organization of protoplasm; 

 perhaps life is best described as organization, thus giving it a static 

 rather than a dynamic significance. Whatever name we give it, 

 however, brings us no nearer to a conception of what it actually is, 

 for life cannot be measured and endures until its organization is 

 disintegrated. With vitality the case is different; here we have to 

 do with protoplasm in motion and the activities can be measured 

 from beginning to end of a life cycle. While life has evidently been 

 continuous from the first protoplasmic organization, vitality has 

 been intermittent or discontinuous. Life may exist without vitality 

 and has always the potential possibility of vitality, but vitality is 

 impossible without organization, i. e., without life. I would define 

 vitality, therefore, not as the same thing as life, but as the sum total 

 of actions, reactions and interactions between and amongst the 

 substances making up the organization of protoplasm and between 

 these and the environment. It is in this sense that the term vitality 

 will be used in the following pages (see Chapter X). 



