TRANSFORMISM 221 



which are inherited and those which are acquired ; 

 but the majority of biologists did not hesitate to con- 

 clude that not only was the transmission of acquired 

 characters an unproved conjecture, but that it was 

 even theoretically inconceivable. At the beginning 

 of the nineteenth century this belief had almost become 

 a doctrine dogmatically asserted, and one cannot fail 

 to notice a tone of irritation and impatience on the 

 part of the spokesmen of zoology when the contrary 

 opinions are expressed. " Nature," says Sir E. Ray 

 Lankester, " (and there's an end of it) does not use 

 acquired characters in the making and sustaining of 

 species for the very simple reason that she cannot 

 do so." 



There can be little doubt that the interrogation 

 of nature with regard to this question was not a very 

 thorough process. The dogmatic denial of the trans- 

 mission of acquired characters was not the result of 

 exhaustive experiment and observation, but was due 

 rather to the very general acceptance in England and 

 Germany of Darwin's hypothesis of the transmutation 

 of species by means of natural selection, and of Weis- 

 mann's hypothesis of the continuity of the germ-plasm. 



The newer hypothesis of transmutation was one 

 which seemed adequate to account for the diversity 

 of forms of life, so that it was unnecessary to invoke 

 the older one ; though Darwin himself admitted that 

 the individual acquirement of structural modifications 

 might be a factor in the evolutionary process ; and 

 for more than twenty years after the publication of 

 the " Origin of Species ' Lamarck's hypothesis was 

 not strenuously denied by naturalists. Early in the 

 'eighties, however, Weismann published his book on 

 the germ-plasm, and the brilliancy and constructive 

 ability of the speculations contained in this remarkable 



