BiOTic State of Energy 109 



able temperature, water and oxygen supply, the metabolism 

 of stored food; which also, in contrast to the shed leaves and 

 flowers, can resist extremes of temperature up to 60-65° C, 

 or as low as — 30° C, and yet, on return of favorable conditions, 

 start into full activity of growth. 



Now if such plants be kept so environed that they are exposed 

 not for a few months but for years continuously to such dor- 

 mant states, a stage is reached — as at times happens in hot 

 countries that for years may have no appreciable rainfall — 

 when the protoplasm fails to remain sufficiently energized, 

 and the organism disrupts in its living machinery. 



Throughout all the phases of this process there is a contin- 

 uous flow of some form of energy, as is proved by the slow 

 utilization of reserve starch or oil during the process. Were it 

 electric energy, the plants would reveal such in disrupting 

 their reserve supply, unless we suppose that it is steadily dis- 

 charged into the earth. Or, were it chemic energy, the plants 

 would be denuded of their reserve food supplies, which often 

 is by no means the case. But the abundant supply, the labile 

 character, the resisting capacity, and the persistent flow for 

 months or even years of the kind of energy here involved, all 

 indicate that we have to deal with a more perfect and condensed 

 exhibition of energy than those of inorganic bodies, but which 

 after expending itself for a certain period becomes exhausted, 

 and then, though reserve food be still present in abundance, 

 death of the plant occurs. 



Again in not a few tissue-cells of higher plants, that are 

 alive and perform mainly a vegetative function, the nucleus 

 may be absorbed, the protoplasm may alone remain, and yet 

 vegetative functional activity may continue. Such are seen 

 in sieve-tubes, in many latex cells, apparently also in some 

 food-storing cells of tubers and seeds. In the case of sieve- 

 tubes even, a seasonal variation in formation of plate-callus 

 towards the close of each season may alternate T\-ith digestion 

 and resorption of the callus substance at the beginning of the 

 next seasonal growth. In all of these cases a slow and steady 

 vegetative activity is shoTvn by the protoplasm, at the same 



