CONTENTS 



CHAPTER I 



PAGE 



The Problem of Adaptation i 



Structural Adaptations i 



Adjustments of the Individual to Changes in the Environment . 12 



Adaptations for the Good of the Species 19 



Organs of Little Use to the Individual 22 



Changes in the Organism that are of No Use to the Individual 



or to the Race 25 



Comparison with Inorganic Phenomena 26 



CHAPTER II 



The Theory of Evolution 30 



Evidence in Favor of the Transmutation Theory ... 32 

 Evidence from Classification and from Comparative Anat- 

 omy .......... 32 



The Geological Evidence 39 



Evidence from Direct Observation and Experiment . . 43 



Modern Criticism of the Theory of Evolution ... 44 



CHAPTER III 



The Theory of Evolution (continued') 58 



The Evidence from Embryology 58 



The Recapitulation Theory ...... 58 



Conclusions 84 



CHAPTER IV 



Darwin's Theories of Artificial and of Natural Selection 91 



The Principle of Selection 91 



Variation and Competition in Nature 104 



The Theory of Natural Selection . . . . . .116 



xi 



