xii CONTENTS 



CHAPTER IX 



WAENING COLORATION AND MIMICRY 



The skunk as an example of warning coloration — "Warning colours among 



insects— Butterflies — Caterpillars — Mimicry — How mimicry has been 

 produced — Helicouidse — Perfection of the imitation — Other cases of 

 mimicry among Lepidoptera — Mimicry among protected groups— Its 

 explanation — Extension of the principle — Mimicry in other orders of 

 insects — Mimicry among the vertebrata — Snakes — The rattlesnake and 

 the cobra — Mimicry among birds — Objections to the theory of mimicry 

 — Concluding remarks on warning colours and mimicry 



Pages 232-267 



CHAPTER X 



COLOURS AND ORNAMENTS CHARACTERISTIC OF SEX 



Sex colours in the moUusca and Crustacea — In insects — In butterflies and 

 moths — Probable causes of these colours — Sexual selection as a 

 supposed cause — Sexual coloration of birds — Cause of dull colours of 

 female birds — Relation of sex colour to nesting habits — Sexual colours 

 of other vertebrates — Sexual selection by the struggles of males — 

 Sexual characters due to natural selection — Decorative plumage of 

 males and its efi'eet on the females — Display of decorative plumage 

 by the males — A theory of animal coloration — The origin of accessory 

 plumes — Development of accessory plumes and their display — The 

 efi'eet of female preference will be neutralised by natural selection — 

 General laws of animal coloration — Concluding remarks , 268-300 



CHAPTER XI 



THE SPECIAL COLOURS OF PLANTS : THEIR ORIGIN 

 AND PURPOSE 



The general colour relations of plants — Colours of fruits — The meaning of 

 nuts — Edible or attractive fruits — The colours of flowers — Modes of 

 securing cross-fertilisation — The interpretation of the facts — Summary 



