TABLE OF CONTENTS 
xi 
PART III. THE CAUSAL FACTORS OF ORGANIC EVOLUTION 
CHAPTER XIII. INntRopuctory STATEMENT 
What We Owe to Darwin 
CHAPTER XIV. THE BACKGROUND oF DaRrwinisM— 
Apaptations. H.H.N.. 
Laws of Adaptation . 
Adaptations Classified 
Some Special Adaptations 
Parasitism and Degeneration 
Color in Animals . 
CHAPTER XV. THE BACKGROUND OF DARWINISM—Continued 
The Web of Life. J. Arthur Thomson 
CwaPTeR XVI. Natural SELECTION. Charles Darwin . 
Foundation Stones of Natural Selection 
Darwin’s Own Estimate as to the Roéle of Natural Selection 4 in 
Evolution . 
Effects of Habits and ‘the Use 0 or Disuse of Pavia ‘Comeluted 
Variation; Inheritance . 
Darwin’s Idea of the Causes Bespansiile for the Caen of Temes: 
tic Races . 
Darwin’s Idea of the Origin of Varieties, Species, and Genera 4 in 
Nature 
The Term “Struggle for Existence” ‘Used e a Large Sense’. : 
Geometrical Ratio of Increase 
Natural Selection; Or the Survival of the Fittest 
Sexual Sélection 
Tllustrations of the Action of ‘Natural Selection, or © the Shevivall 
of the Fittest . . 
Summary of Chapter on Natural Bdevtion, 
Difficulties and Objections to Natural Selection as Seen ye ‘Darwin 
CHAPTER XVII. CriTIQUE OF DARWINISM . ‘ 
Summary of Darwin’s Natural-Selection haar Veins a 
Kellogg . : 
Objections to Darwinian, 
Defense of Darwinism 
General Defense of Darwinism. c 4 L. T aie 
Experimental Support of the Effectiveness of Natural Selection 
The Present Status of Natural Selection . 
The Relation of Mendelism and the Mutation Theory to Natural 
Selection. C.C. Nutting . gO} 4 OR OS 
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