X PRE FA CE 



the evolution theory may, at no distant date, be re- 

 printed in the original, as they are not bulky and 

 could be comprised in a single volume. 



This life is offered with much diffidence, though 

 the pleasure of collecting the materials and of put- 

 ting them together has been very great. 



Brown University, Providence, R. I., 

 October, igoi. 



