cox, DARWIN AND THE MUTATION THEORY 445 



"One of the most remarkable features in our domesticated races is that we see 

 in them adaptation, not indeed to the animal's or plant's own good, but to man's 

 use or fancy. Some variations useful to him have probably arisen suddenly, or by 

 one step; many botanists, for instance, believe that the fuller's teasel, with its 

 hooks, which can not be rivaled by any mechanical contrivance, is only a variety of 

 the wild Dipsacus ; and this amount of change may have suddenly arisen in a seed- 

 ling." 1 



Surely, if Mr. Danvin could have looked at this case with a perfectly 

 free mind, he must have perceived that the teasel's adaptation to man's 

 needs would not have fallen if man had failed to exercise his power of selec- 

 tion; and that the adaptation was not weakened by the fact that it arose 

 by a mutation. But that he was unconsciously biased in this matter is 

 shown by an extract from a letter written to Asa Gray, in 1860, in which he 

 says : 



" I reflected much on the chance of favorable monstrosities {i. e., great and sudden 

 variation) arising. I have, of course, no objection to this, indeed it would be a great 

 aid, but I did not allude to the subject [i. e., in the 'Origin'] for, after much labor, 

 I could find nothing which satisfied me of the probability of such occurrences. There 

 seems to me in almost every case too much, too complex, and too beautiful adapta- 

 tion, in every structure, to believe in its sudden production." ^ 



The idea involved in this passage is that adaptation is produced — rather 

 than preserved — by natural selection and that, as natural selection must, 

 according to Mr. Darwin's curious prepossession, act only upon slow and 

 small changes of character, adaptation itself must necessarily be in every 

 case a matter of gradual growth. This sort of argument appears to justify 

 the fear shared by both Lyell and Hooker that Darwin was at times dis- 

 posed to stake his whole case on the maintenance of an unnecessary assump- 

 tion. Hooker wrote him as early as 1859 or 1860 that he was making a 

 hobby of natural selection and overriding it, since he undertook to make it 

 account for too much. ^ Darwin mildly protested that he did not see how 

 he could do more than he had done to disclaim any intention of accounting 

 for everything by natural selection. * In this discussion, however, it is 

 apparent that while Darwin was overloading the theory of natural selection 

 with a responsibility for the origin of the adapted or fit, he was at the same 

 time unduly limiting it to only one class of the fit, namely those which had 

 arisen by slow degrees. If he had taken the position that natural selection 

 could and would operate upon any kind or any degree of variability, he need 

 not to have imagined that his main doctrine was in jeopardy. 



1 " Origin of Species," 6th ed., p. 22. 



2 " Life and Letters," 1887, Vol. II. p. 333. 



3 " More Letters," 1903, Vol. I, p. 135. 

 *Ibid., Vol. I, pp. 172, 213. 



