8o THE GERM-PLASM THEORY 



molecules having a complexity of structure as 

 great as that of a molecule of albumen." 



Well has it been observed that 



" the physicists report that the image of a Great 

 Eastern filled with framework as intricate as that 

 of the daintiest watch does not exaggerate the 

 possibilities of molecular complexity in a sper- 

 matozoon, whose actual size may be less than the 

 smallest dot on the watch's face." 



But it is at least fair to remark that the theory 

 is a tolerably complex one to be built up entirely 

 upon a system of " vital units," which no one has 

 ever seen or can ever demonstrate. The author 

 of the theory frankly admits all this, but contends 

 that his assumptions are justified by the facts of 

 nature. Well, let us see what another eminent 

 scientific man has to say on that head. Professor 

 Hertwig of Berlin is a man whose name is known 

 wherever biologists exist. He has no odium theolo- 

 gicum, nor is there any other reason why he should 

 regard the facts as teaching a different lesson, but 

 the reason that Weismann's assumptions are not 

 the kind of assumptions which appeal to him. 

 Let us hear what he says of the views which we 

 have been explaining : 



" When, to satisfy our craving for causality, 

 biologists transform the visible complexity of the 

 adult organism into a latent complexity of the 

 germ, and try to express this by imaginary tokens, 

 by minute and complicated particles coherent 

 into a system, they are making a phantasmal 



