EVOLUTION 



CHAPTER I 

 THE EVOLUTION OF THE IDEA OF EVOLUTION 



THE word " Evolution " is so familiar to everybody 

 to-day that it may seem quite superfluous to delay, even 

 for a page, in making its meaning clear. Great scientific 

 truths that startled even the most thoughtful men little 

 more than half a century ago now fall glibly from the 

 lips of the schoolboy. He knows that all the varied 

 animal and plant forms on the earth are more or less 

 distantly related in the family of nature. He knows 

 that the suns that faintly shine on him through billions 

 of miles of space are all running through a long life 

 story, and he may have a general idea of their career 

 from their cradle in a nebula to their grave in the 

 darkness of space. Even if he has contrived to avoid 

 learning this, he knows that the railway engine has had 

 a long development, and that the British Empire was 

 not formed in a day. 



But let the reader, if he has had no special training 

 in the matter, attempt to tell himself what he means by 

 evolution. He will soon see that he has by no means 

 the clear and definite idea that he thought he had, and 

 that it is extremely desirable to have at the outset of 

 any study whatever. In point of fact, it has cost learned 

 men some effort to say in a few clear words what is 

 meant by the idea of evolution. 



I 



