vi PREFACE. 



have no pretension to be any more than 

 popular expositions of current evolutionary 

 thought, occasionally their author's, oftener 

 still other people's : but they may perhaps 

 do a little good in spreading more widely a 

 knowledge of those great biological and 

 cosmical doctrines which are now revolution- 

 ising the European mind, and which owe 

 their origin to the epoch-making works of 

 Charles Darwin and Herbert Spencer. 



G. A. 



