CHAP, xxv.] CONCLUDING REFLEXIONS. 575 



little how they became so, and rarely telling us how they may be 

 brought together. Thus each class misses that which in the 

 other is good. 



But when once it is seen that, whatever be the truth as to the 

 modes of Evolution, it is by the Study of Variation alone that the 

 problem can be attacked, and that to this study both classes of 

 observation must equally contribute, there is once more a place 

 for both crafts side by side : for though many things spoken of in 

 the course of this work are matters of doubt or of controversy, of 

 this one thing there is no doubt, that if the problem of Species is 

 to be solved at all it must be by the Study of Variation. 



