Law of Proenvironment 221 



With such results before us as above presented, if a wide 

 survey be made of general plant stimulation and response, 

 many resultant phenomena seem to present themselves, though 

 regarding most of them our knowledge is still so elementary 

 that one can do no more than suggest the possibility, in some 

 cases the probability, of their existence. Thus the compounded 

 or resultant forward and also gyratory motions of many sperma- 

 tozoids ; the ascending spiral relation of the successive segment- 

 cells cut off from the apex of most multicellular cryptogams; 

 the successive segmentation of these and equally of the young 

 tissue cells of flowering plants along definite lines, until a def- 

 inite amount of tissue is built up ; even the correlative develop- 

 ment of a certain color, size, shape, degree of insertion on the 

 receptacle, and degree of nectar secretion in certain flowers; 

 seem all to be the product of several stimulant factors united 

 into a resultant response. 



Such responses, in which lines of energy are constantly being 

 set free along definite tracts or pathways, cause a flow of ener- 

 gized molecules toward certain centers and a flow away from 

 other centers. So the functional activities slowly but gradu- 

 ally determine and mold the structural outlines. Structure 

 therefore seems to be the temporarily static expression of 

 many resultant actions and reactions of energized particles, 

 that have become more or less definitely placed in hereditary 

 ])Ositions, through proenvironal response to environal stimuli. 



Before passing from such plant studies to those of animals, 

 we might summarize our position so far by stating that the 

 law of proenvironment seems to have its simplest organic 

 expression in single, simple, and successive responses of the 

 simplest bacteria and Blue-green Algse to the varied environal 

 stimuli by which each is surrrounded. Tliis action, we have 

 suggested, probably owes its origin to the chemical principle 

 of satisfied or unsatisfied chemical molecules, the presence of 

 the latter state in any body constantly causing flows of energy 

 and resulting molecular integration or disintegration. 



But in the higher Acaryophyta, such as the Oscillatoriaceie 

 and Bacteriaceie, evident intrinsic compounding of two or more 



