216 CORRESPONDENCE [September 1898 



and because conditions are usually more powerful, and necessarily operate for shorter 

 periods of time, when under man's direction than in nature, so variations should be 

 correspondingly less definite in the domesticated forms of life. 



This position also destroys the force of the two chief arguments used against Natural 

 Selection by demonstrating that it is itself able to induce those favourable variations, which 

 it subsequently selects from. Firstly, it is urged that Natural Selection being unable to 

 produce definite variations must be dependant on some other factor until the 

 variations are sufficiently far advanced to be of selective value, and it is therefore in- 

 competent to solve the most important question in the formation of species ; secondly, 

 the number of coincidences, which are necessary to perpetuate any given favourable varia- 

 tion on the assumption of indefinite variability, are so great that Natural Selection must 

 be regarded, at best, only as a subordinate factor. By showing that, if natural selec- 

 tion acts at all, it must tend to produce definite variations, these two objections are 

 largely overcome, and the facts adduced by the Neo-Lamarckian school easily accounted 

 for. Hence with two competing theories to explain species formation, it becomes neces- 

 sary to make a further appeal to facts to determine the value of each. 



I feel so convinced of the importance of this aspect of the subject that I should be 

 sorry if any want of clearness on my part at all obscured the point at issue. 



J. Lionel Tayler. 



The Grotto, Hampton-on-Thames. 



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