CHAPTER IX. 



EFFECTS OF REORGANIZATION AND THE ORIGIN OF 

 VARIATIONS IN THE PROTOZOA. 



In the preceding chapters we have developed the ideas that life 

 is organization plus its activity; that vitality is the sum total of 

 actions, reactions and interactions between and amongst the aggre- 

 gate of substances which make up protoplasm; that minute differ- 

 ences in the aggregate of substances constitute differences in organ- 

 ization; that no two organizations are identical; that with continued 

 metabolism the protoplasm of a given individual undergoes changes 

 in organization which are gradual but progressive; that such changes 

 may be manifested by structural differentiations and by physio- 

 logical activities which are characteristic of certain periods in the 

 life cycle; and that progressive differentiation leads to a condition 

 or protoplasmic stability such that metabolic activities weaken or 

 cease altogether. 



We have no desire to belittle or ignore the fact that observations 

 are not all in accord with the conclusions outlined above or to under- 

 estimate the significance of data which apparently do not agree 

 with them. We are attempting however, to formulate a conception 

 of organization and vitality which will embrace as large a field of 

 observational results as possible and to give a rational interpretation 

 of them. An important part of such an interpretation is concerned 

 with the effects of fertilization and parthenogenesis which are 

 briefly considered in the present chapter. 



I. EFFECTS OF REORGANIZATION ON VITALITY. 



If our fundamental thesis that continued metabolism leads to 

 functional weakening and ultimate cessation of vitality is correct 

 it follows that for continued life some reconstructive or reorganizing 

 operation is necessary. The phenomena attending cell division, 

 together with experimental evidence (see Chapter VI), indicate that 

 such reorganization may occur with each division of the cell, and 

 that vitality of the protoplasm immediately after division is nor- 

 mally unhampered by accumulated products of activity in the form 

 of metaplastids or of substances which are becoming inert. The 

 deep-seated changes in organization which accompany fertilization 

 and parthenogenesis have a similar but even more profound effect, 

 for the protoplasm is entirely made over and new cell organs are 



