EVOLUTION AND HEREDITY. 1 39 



the question of inheritance of acquired characters, they 

 are almost but not quite in accord ; Galton is in doubt, 

 Weismann thinks it improbable if not impossible. From 

 the standpoint of evolution, or non-repetition, however, 

 there is one point in which Galton's results are de- 

 cidedly adverse to Weismann as we shall see. 



There is thus strong evidence for the ''continuity of 

 the germ plasm" theory. This does not seem to be 

 necessarily antagonistic to the Lamarckian idea for we 

 can conceive that the germ plasm is continuous and still 

 influenced in definite ways by the body which contains 

 it. Yet Weismann holds that this is not the case: that 

 no special or local life changes in the body can in any 

 way reach or influence the germ cells in such a man- 

 ner as to be inherited. This view throws the whole 

 burden of evolution upon the natural selection or sur- 

 vival of those individuals which possess, by blending 

 or otherwise, that germ plasm which represents the 

 bodily constitution and structure best fitted to environ- 

 ment. 



In this manner the principle of inheritance of acquired 

 characters, from being one of the dogmas of science has 

 been first questioned, then thrown in doubt, and finally 

 rejected by a large body of zoologists. We really owe 

 it to Weismann that this principle, which forms the 

 mainstay of Lamarckism, was adopted by Darwin as a 

 most important factor in evolution, but has never been 

 critically examined from the heredity side, should now be 

 thoroughly investigated. The existence of this principle 

 in inheritance is the focal point of a discussion in which 

 the authority of Lamarck, Darwin, Spencer, Eimer, 

 and the greater number of American biologists may 



