WEISMANN'S THEORY OF THE GERMPLASM 85 



adult body possessed of definite character and of 

 definite position in the body in fact, every group 

 of cells that is independently variable is represented 

 in the egg and in the spermatozoon by a number of 

 little particles - - the biophores - - and that these, 

 joined in a system, form the determinants. The 

 innumerable determinants, he thinks, are so 

 arranged in the germplasm, and are endowed with 

 such powers, that, during the process of develop- 

 ment, they reach, at the right time, the right place 

 for their expansion into cells. For instance, in the 

 case of a mammal with parti-coloured fur, as many 

 architecturally arranged determinants would be 

 present as there were different spots and stripes in 

 the fur, due to colour and length of the hairs. 



This chain of ideas, made sharp and definite by 

 Weismann, has recurred again and aofain in theo- 



7 O O 



retical biological literature in a vague way. In my 

 view, it rests upon a false use of the conception of 

 causality, and upon a false implication given to the 

 relation between the rudiment and the product of 

 the rudiment, each mistake involving the other. 



o 



Because, if its development be not interfered with, 

 a definite egg necessarily gives rise to a definite 

 kind of animal, a complete identity between the 

 rudiment and the product, between cause and con- 

 sequence, has been assumed more or less con- 

 sciously. The conception of the sequence has been 

 as if an organism caused its own development in a 

 closed system of forces, in a kind of organic per- 

 petual motion. It has been overlooked that, in 

 the course of the development, many other con- 



