x Preface 



to regenerate; and it seemed to me, therefore, desirable to 

 reexamine the whole question of adaptation, for might it 

 not prove true here, also, that the theory of natural selection 

 was inapplicable ? This was my starting-point. The results 

 of my examination are given in the following pages. 



I am deeply indebted to Professor G. H. Parker and to 

 Professor E. G. Conklin for advice and friendly criticism; 

 and in connection with the revision of the proof I am 

 under many obligations to Professor Joseph W. Warren 

 and to Professor E. A. Andrews. Without their generous 

 help I should scarcely have ventured into a field so full of 

 pitfalls. 



Bryn Mawr, Penn., June 10, 1903. 



