CONTENTS 



SECTION III 



PACE 



INFLUENCE OP ADAPTATION IN THE FORMATION OF SPECIES 63 



Is everything adapted 1 . . . .63 



Death as an Adaptation . . . . .67 



Further Considerations on the Adaptation and Direction of 



Evolution of the Markings of Caterpillars. Absence of 



Sexual Combination in this Evolution . . .72 



Characters which are inessential (indifferent) to the Life of the 



Organism ...... 74 



SECTION IV 



ACQUIRED CHARACTERS 78 



Methods of Investigation The Period of Time to be claimed 



for Evolution . . . . .78 



Acquired Characters due to Direct External Action . . 87 



Experiments on the Influence of Temperature on Lepidoptera . 116 

 Further Remarks on the Causes which Change the General 



Colouring of Animals . . . . .135 



Influences of Locality on the Variation of Animals, and thereby 



on the Formation of Species . . . .139 



Importance of the Stimulation of the Nervous System in 



relation to Adaptation and the Origin of Species . 142 



Particular Facts which prove the Influence of Nutrition and 

 other external Conditions on the Variation and Formation 

 of Species in Lepidoptera . . . .149 



Characters acquired by Use . .153 



Inheritance of Injuries and Diseases . . . .173 



SECTION V 



DISUSE OF ORGANS DEGENERATION PAMMIXIS 205 



Pammixis . 217 



