Xll PREFATORY NOTE TO ENGLISH EDITION 



windmills. But, above all, the book will be valued by workers 

 in many departments of Biology, who are trying to help 

 in the evolution of Evolution Theory, for it is characteristic 

 of the author, as the history of recent research shows, to 

 be suggestive and stimulating, claiming no finality for his 

 conclusions, but urging us to test them in a mood of ' thatige 

 Skepsis.' 



The translation of this book — the burden of which has 

 been borne by my wife — has been a pleasure, but it has also 

 been a serious responsibility. We have had fine examples 

 set us by previous translators of some of Weismann's works, 

 Meldola, Poulton, Shipley, Parker, and others ; and if we 

 have fallen short of their achievements, it has not been for 

 lack of endeavour to follow the original with fidelity, nor for 

 lack of encouragement on the part of the author, who revised 

 every page and suggested many emendations. 



J. AETHUE THOMSON. 



University of Aberdeen, 

 October, 1904. 



