CONTENTS 
CHAPTER I 
RIsE OF THE THEORY OF NATURAL SELECTION AND 
ITS SUBSEQUENT DEVELOPMENT . ‘ i I 
PAGE 
Pre-Darwinian Evolutionists—Causes which led to the speedy triumph 
of the theory of Natural Selection—Nature of the opposition 
which Darwin had to overcome—Post-Darwinian biology— 
Usually accepted classification of present-day biologists as Neo- 
Lamarckians and Neo-Darwinians is faulty—Biologists fall into 
three classes rather than two—Neo-Lamarckism : its defects— 
Wallaceism: its defects—Neo-Darwinism distinguished from 
Neo-Lamarckism and Wallaceism—Neo-Darwinism realises 
the strength and weakness of the theory of Natural Selection, 
recognises the complexity of the problems which biologists are 
endeavouring to solve. 
CHAPTER II 
SOME OF THE MORE IMPORTANT OBJECTIONS TO THE 
THEORY OF NATURAL SELECTION . , 30 
Brief statement of Theory—Objections to the Theory fall into two 
classes—Those which strike at the root of the Theory—Those 
which deny the all-sufficiency of Natural Selection—Objections 
which strike at root of Theory are based on misconception— 
Objections to Wallaceism—The Theory fails to explain the 
origin of Variations—Natural Selection called on to explain too 
much—Unable to explain beginnings of new organs—The 
Theory of change of function—The co-ordination of variations 
—The fertility of races of domesticated animals—Missing links— 
Swamping effects of intercrossing—Small variations cannot 
have a survival value—Races inhabiting same area—Excessive 
specialisation—Chance and Natural Selection—Struggle for 
existence most severe among young animals—Natural Selection 
fails to explain mimicry and other phenomena of colour— 
Conclusion, that scarcely an organism exists which does not 
possess some feature inexplicable on the theory of Natural 
Selection as held by Wallace and his followers. 
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