Art and Science 



that changes induced by external conditions 

 in the organism as a whole are communicated 

 to the germ-cells after the manner indicated in 

 Darwin's hypothesis of pangenesis, is wholly 

 unnecessary for the explanation of these pheno- 

 mena. Still we cannot exclude the possibility 

 of such a transmission occasionally occurring, 

 for even if the greater part of the effects must 

 be attributable to natural selection, there might 

 be a smaller part in certain cases which depends 

 on this exceptional factor." 



I repeatedly tried to understand Mr. Dar- 

 win's theory of pangenesis, and so often failed 

 that I long since gave the matter up in despair. 

 I did so with the less unwillingness because I 

 saw that no one else appeared to understand 

 the theory, and that even Mr. Darwin's 

 warmest adherents regarded it with disfavour. 

 If Mr. Darwin means that every cell of the 

 body throws off minute particles that find 

 their way to the germ-cells, and hence into 

 the new embryo, this is indeed difficult of 

 comprehension and belief. If he means that 

 the rhythms or vibrations that go on cease- 

 lessly in every cell of the body communicate 



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