NATURAL SELECTION 49 



Huxley's independent views on evolution 

 were what we should expect from a great 

 student of animal structure rather than of animal 

 life, who was at the same time a profound and 

 cautious thinker. Huxley told us that before 

 the appearance of the " Origin " he took his stand 

 upon two grounds first, that up to that time the 

 evidence in favour of transmutation was wholly 

 insufficient; and, secondly, that no suggestion re- 

 specting the causes of the transmutation which 

 had been made was in any way adequate to ex- 

 plain the phenomena. And yet all along there 

 was alive in him a sort of pious conviction that 

 evolution would turn out true, and the kind of 

 evolution he imagined was, so far as we were able 

 to judge, a conception which would arise in the 

 mind of one who compared animal structures with 

 the eye and brain of the artist or engineer rather 

 than of the naturalist. At the age of twenty-six he 

 wrote to W. S. Macleay ; " I am every day be- 

 coming more and more certain that you were on 

 the right track thirty years ago in your views of 

 the order and symmetry to be traced in the true 

 natural system." Macleay's ideas of the grouping 

 of the animal kingdom were about as regular and 

 symmetrical as the figures seen in a kaleidoscope. 

 And a conception of sharply separated mathe- 

 matically grouped forms would naturally lead to 

 the idea of evolution by sharp and abrupt steps, 

 whereby a new form would appear by sudden 

 transformation of the old, just as a chemical com- 



