PREFATORY NOTE TO ENGLISH EDITION 



Professor Weismann's Evolution Theory, here translated 

 from the second German edition (1904), is a work of com- 

 pelling interest, the fruit of a lifetime of observation and 

 reflection, a veteran's judicial summing up of his results, and 

 certainly one of the most important contributions to Evolution 

 literature since Darwin's day. 



As the author's preface indicates, the salient features of 

 his crowning work are (1) the illumination of the Evolution 

 process with a wealth of fresh illustrations ; (2) the vindica- 

 tion of the ' Germ-plasm ' concept as a valuable working 

 hypothesis ; (3) the final abandonment of any assumption of 

 transmissible acquired characters ; (4) a further analysis of 

 the nature and origin of variations ; and (5), above all, an 

 extension of the Selection principle of Darwin and Wallace, 

 which finds its logical outcome in the suggestive theory of 

 Germinal Selection. 



The translation will be welcomed, we believe, not only 

 by biological experts who have followed the development of 

 ' Weismannism ' during the last twenty years, and will here 

 find its full expression for the time being, but also by those 

 who, while acquainted with individual essays, have not 

 hitherto realized the author's complete system. Apart from 

 the theoretical conceptions which unify the book and mark 

 it as an original contribution of great value, there is a lucid 

 exposition of recent biological advances which will appeal to 

 those who care more for facts than theories. To critics of 

 evolutionism, who are still happily with us, the book ought 

 to be indispensable ; it will afford them much material for 

 argumentation, and should save them many tilts against 



