Art and Science 



when and where we can watch them. Nature 

 is eminently conservative, and fixity of type, 

 even under considerable change of conditions, 

 is surely more important for the well-being 

 of any species than an over-ready power of 

 adaptation to, it may be, passing changes. 

 There could be no steady progress if each 

 generation were not mainly bound by the 

 traditions of those that have gone before it. 

 It is evolution and not incessant revolution 

 that both parties are upholding; and this 

 being so, rapid visible modification must be 

 the exception, not the rule. I have quoted 

 direct evidence adduced by competent ob- 

 servers, which is, I believe, sufficient to 

 establish the fact that offspring can be 

 and is sometimes modified by the acquired 

 habits of a progenitor. I will now pro- 

 ceed to the still more, as it appears to me, 

 cogent proof afforded by general considera- 

 tions. 



What, let me ask, are the principal phe- 

 nomena of heredity ? There must be physical 

 continuity between parent, or parents, and 



offspring, so that the offspring is, as Erasmus 



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