Active Causes of Organic Evolution 189 



as well as the rapid changes in some cases, and slow changes 

 in others that various metals as well as other inorganic bodies 

 undergo, the above definition, if modified as suggested, would 

 exactly and appropriately include all "bodies." Shortly defined 

 the law might be expressed as: the summated action of all ex- 

 ternal agents on any body. 



(3) Proenvironment. We pass now to the consideration 

 of an evolutionary factor that hitherto has been entirely over- 

 looked, but which takes high rank alongside the above two. 

 When we say that it has been entirely overlooked, we mean 

 for the organic world as a great whole. But Kidd, in his two 

 most suggestive volumes, "Social Evolution" and "Principles 

 of Western Civilization," has closely approached the factor 

 for man, though he has failed to trace its gradual evolutionary 

 advance from plants up through all stages of animal life to 

 Man, and has also failed in reciting the fundamental phenomena 

 that start and continue the factor. We propose to term it 

 the law of proenvironment or prosynergy. 



Its far-reaching importance can perhaps scarcely be esti- 

 mated as yet, owning to our imperfect knowledge of some of 

 the simpler organisms, notable the Blue-green Algge. We can 

 select first, for experimental illustration, some germinating 

 plant embryos, and conveniently those of the common broad 

 bean or pea, whose roots are pushing out through the seed 

 coat. The colorless radicles first protrude, and, in virtue of 

 their being influenced or stimulated hereditarily by gravity, 

 by moisture, by soil contact or friction, and by negative lumic 

 relation at least, these all grow directly into the earth. But 

 suppose three seeds to have been purposely so placed under 

 shaded bell-jars (Fig. 3, a, b, and c) above plates filled with 

 water that their radicles are illuminated from one side, and two 

 are placed transversely; further that one of the two is exposed 

 to the uniformly moistened atmosphere of the jar interior, 

 while the other has a steadily moistened sponge hung near and 

 above it. As all who have had even an elementary course in 

 practical plant physiology know, three totally different path- 

 ways \vi\\ be determined on and accurately pursued, by the 



