SYNTHESIS 'AND EVOLUTION 



The processes of evolution have not increased in 

 plants the development of what may be called the 

 mental forces of nature. The tendency of the roots 

 of growing plants towards water, the grasping of the 

 tendrils of a vine for the support needed for its 

 growth, the varied phenomena of florescence and re- 

 production, indicate no more of volition than the pro- 

 tococus or vaucheria have shown. The functions to 

 be carried on in the plant world, that of preparing 

 food, liberating oxygen, and of thus rendering animal 

 life possible by their previous existence, need no ad- 

 dition of increased duties or higher faculties than we 

 find plants gifted with. 



The processes of plant life are essentially syn- 

 thetical. They form from the inorganic molecules 

 of the soil air and water, those compounds of carbon, 

 hydrogen and other elements which, when reunited, 

 make the plasmodium, tissues and fluids of cellular 

 structures that constitute the food of animals. They 

 give out to the air the oxygen they have set free from 

 its chemical union with carbon and with hydrogen to 

 become later the source of breathing for all animal 

 life. On the other hand, the metamorphoses in the 

 animal are essentially the opposite, the retrogressive 

 and oxidizing, whereby one part of the tissues and 

 substances formed in the animal from the food pre- 

 pared by plant life runs down the plane of organiza- 



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