HEREDITY AND VARIATION 228 



until she has those facts it would be mere 

 foolishness to attempt to arrive at conclusions. 

 All, therefore, that we can safely say here is 

 that, in spite of the views which have been 

 tentatively put forward as to a process of 

 evolution which may be taking place in the 

 inorganic world, and which might, if true, 

 point to some form of variation being found 

 there, observation plainly shows us that rigi- 

 dity of operation is the main characteristic of 

 that kingdom ; variation of the other. And, 

 from what we have observed on other points, 

 we shall certainly not be surprised if the cause 

 of variation is oLa jjurely vitalistic character. 



