FORMS OF LIVING-MATTER UNITS 105 



kind, no matter how complex, have a form of equi- 

 librium in which, when they aggregate, their complex 

 forces are balanced a form far less rigid and de- 

 finite, for the reason that they have far less definite 

 polarities, are far more unstable, and have their ten- 

 dencies more easily modified by environing conditions. 



Weismann himself admits that if the power of 

 repair and regeneration after injury, possessed to 

 such a remarkable extent by so many of the lower 

 animals, is dependent upon a ' primary power ' 

 rather than upon one that has been ' acquired by 

 Natural selection," he would have to give up his 

 position, and therefore nearly all the hypotheses 

 with which his name is associated. He says : * 



In truth, if the body was really able to replace, 

 after artificial injury, parts which were never liable 

 to injury in natural conditions, and to do so in a 

 most beautiful and appropriate manner, then there 

 would be nothing for it but at least to regard the 

 faculty of regeneration as a primary power of living 

 creatures, and to think of the organism as like a 

 crystal, which invariably completes itself if it be 

 damaged in any part. 



But, according to Loeb, Driesch, Oscar Hert- 

 wig, and many others, merotomy experiments, the 



1 The Evolution Theory, 1904, vol. ii. ; p. 19. 



