108 Causes and Course of Organic Evolution 



linking, and holding them together, the energy that has done 

 this is the truly Important agent, no matter though we may 

 have difficulty in isolating it, or studying it apart from its 

 material consort and conductor. Now, since work of high 

 complexity is done in such cells \\'ith comparative ease and 

 by high utilization of energy in the process, we believe that 

 the recognition of a biotic energy as typical of the Acaryota 

 will help us greatly toward a true interpretation of their life 

 changes. 



We may now attempt to secure e\adences for the existence 

 of a biotic energy in nucleate or chromatin-forming plants. 

 Here, however, if our views are correct, we must ever bear in 

 mind that the union of protoplasm and chromatin represents 

 the correlative display of biotic and cognitic energy. So for 

 demonstration of the continued action of the former energy 

 we must either be able to observe nucleate plants under con- 

 ditions where one of these energies mainly is in evidence, or 

 to analyze up each, apart from its constituent energy. Both 

 methods seem helpful and possible. 



In nearly all land plants, and particularly in those which 

 are exposed to marked seasonal changes of hot and cold weather, 

 or of dry and moist states, there are alternate periods when 

 each plant shows what might be called an active and a passive 

 phase, a growing and a dormant seasonal condition. Thus 

 in temperate regions^, at the close of the gromng season of the 

 year, the more actively responsive parts, such as the leaves, 

 the flowers, and even young twags, fall to the ground. Through- 

 out the wdnter and early spring, active response to environal 

 stimuli has ceased, but the plant is not dead. Nor is it merely 

 a passive inert mass of chemical material, for the protoplasm 

 and reserve food do not decay; they are not readily invaded 

 by fungi as masses of inert chemical food would be; on warm 

 days even the protoplasm may show "vital" activity and start 

 sap-flow. In other words there is some reserve of energy in 

 the comparatively sluggish or dormant cells, which causes 

 continued energizing of the protoplasmic and protein mole- 

 cules; which may set free and start, on short exposure to suit- 



