HEREDITY AND ENVIRONMENT 193 



to be an essential factor. His instincts, and his knowledge 

 of activating principles and processes, appear to have led 

 him right after all. Activating elements are supplied 

 fully developed by the parents who took uncounted 

 ages to acquire them. There is no reason whatsoever 

 for not endorsing Starling's almost wistful statement, 

 although in some moment of doubt he rejected it at last. 

 If the elements themselves show that in a like temperature- 

 environment they stay the same, and change when it 

 changes, and yet go back when it again alters, no more 

 is asked by any advocate of transmission. We may even 

 say," as I have suggested elsewhere, 1 that the whole course 

 of evolution suggests that what we have to discover is not 

 why child is like parent but why, in certain cases, it is 

 unlike, being sure as we pass to the investigation that some 

 internal or external environmental cause is at the bottom 

 of the alteration. Belogolovy bred ova of the frog 

 Pelobates in the parental body cavity. Their " deter- 

 minants " determined nothing as the ova became para- 

 sitic and presented highly abnormal characteristics, not 

 Pelobatic at all. Such considerations may no doubt 

 be dismissed as purely theoretical, or even excursions of 

 the fancy ; but if it is noted that the greatest weakness 

 to which all scientific men are liable is the natural tendency 

 to take the easiest path, and ignore general principles, 

 they may not seem so much out of place. The easiest 

 path at a given time is not always the right one. We 

 may get very doubtful adaptation to facts, for energy 

 over the pyramidal tract does not work with the same 

 certainty as adrenalin. 



If the orthodox school could give any hint as to how 

 a variation is to be explained, and what it is that is changed 



1 Vide Repair in Evolution. 

 13 



