The American Naturalist 



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Price List (No- 11) of Bird Skins. This 

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Fifty Years of Darwinism 



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CONTENTS : Introdr 

 berlin, Walker Museum ; Fifty Years of Dar- 

 winism, Edward B. Poulton,Oxford University; 

 TheTheorv of Natural Selection from the Stand- 

 point of Botany, John M. Coulter, University 

 of Chicago ; Isolation as a Factor in Organic 

 Evolution, David Starr Jordan, Stanford Uni- 

 versity ; The Cell in Relation to Heredity and 

 Evolution, Edmund B. Wilson, Columbia Uni- 

 versity ; The Direct Influence of Environment, 

 Dr. D. T. MacDougal, Carnegie Institution of 

 Washington ; The Behavior of Unit-Characters 



Mutation. Chas. B. Davenport, Station for Ex- 

 Adaptation, Carl H. Eigenmann, Indiana Uni- 

 versity; Darwin and Paleontology, Henry Fair- 

 field Osborn, Columbia Cmver*-' E . it - > 

 a nd Psychology, G. Stanley Hall, Clark Uni- 



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