80 SYMBWGENESIS 



is preferable to a "structural" conception although, of 

 course, Prof. Klebs would scarcely deny that there are dynamic 

 influences underlying structure. Structure, indeed, follows in 

 the wake of dynamics, i.e., of conduct which involves 

 relatedness and dynamic action and reaction. That structure 

 often arrives in a belated manner as a result of new behaviour 

 voluntary or involuntary and, therefore, is not always the 

 most reliable index of the true state of affairs, is otherwise 

 fully recognised by Prof. Klebs. Thus speaking of some arti- 

 ficial interferences with the growth of plants, he states that the 

 transformations of flowers thus induced become apparent about 

 two months after the period when the particular cause began 

 to act. "There is, therefore," he says, "no close connection 

 between the appearance of the modifications and the external 

 conditions which prevail at the moment. When we are 

 ignorant of the causes which are operative so long before the 

 results are seen, we gain the impression that such variations as 

 occur are spontaneous or autonomous expressions of the inner 

 nature of the plant. It is much more likely that, as in 

 Sempervivurn, they were originally produced by an external 

 stimulus which had previously reached the sexual cells or the 

 young embryo." (Italics mine.) 



All of which, although only drawn from individual cases, 

 also refers to influences affecting a species. We are left to 

 ponder over the relation of the " inner nature " of the plant to 

 stimuli from outside. This relation somehow in the long run, 

 we must assume, determines the definite tendencies of species 

 and varieties. Whatever mysteries may be hidden in the 

 "inner nature" of organisms, however miraculous the power 

 of response, and however powerful the influence of the environ- 

 ment, I maintain that what count most in determining the 

 main issue, i.e., the definite tendency, the predominant 

 behaviour and the success or otherwise of a species or a variety 

 are the bio-economic factors. It is not for nothing that a 

 variety responds " spontaneously " in one direction or another; 

 its response is really largely pre-determined by its bio-economic 



