CONTENTS. Vll 



CHAPTER V. 



PROTECTIVE MIMICRY. 



Mr. Bates' Theory.— Mimicry often found only in Females. — Are the 

 Danaidse strongly scented, like the Heliconidie ? — Distastefulness 

 sometimes limited to a Few Individuals. — Resistent Structure of the 

 Wings in Danaids an Additional Defence. — Mimicry between Pro- 

 tected Forms. — Mimicry between Insects belonging to Different 

 Orders. — A Protected Insect sometimes Mimicked by more than 

 one Species. — Mimicry of Vertebrates by Insects and of Insects by 

 Vertebrates. — Mr. Wallace's statement of the Conditions under which 

 Protective Mimicry occurs. — Objections to the Theory of Mimicry. — 

 Resemblances among more or less remotely allied Animals which 

 perhaps cannot be put down to Mimicry. — Instances of Developing 

 Mimicry in Butterflies. — Butterflies more attacked by Birds in the 

 Tropics than in Temperate Regions. — Spiders mimicking Ants. — 

 Difficulty of distinguishing between Mimicry and Warning Colora- 

 tion. — Resemblances between Insects occurring in Different Countries. 

 — Mimicry possibly originated between forms much alike to start 

 with. — Cases of apparently Useless Mimicry. — Mimicry of Hymeno- 

 ptera by Volucella is Difficult to account for. — Vision of Insects. — 

 Cases of Mimicry in which the Mimicking Form is equally abundant 

 with the Model. — Criticism of an apparent case of Mimicry. — 

 Mimicry in some cases possibly only a Resemblance due to Affinity. 

 — Mimicry among Mammals. — Mimicry among Birds. — Mimicry may 

 be in certain oases even Disadvantageous. — Mimicry not always De- 

 ceptive. — The Occasional Limitation of Mimicry to the Female Insect. 

 — Mimicry between Unprotected Forms. — Relative Unimportance of 

 the Imago Stage in Butterflies. — Summary. . . .193 



CHAPTER Vl. 



SEXUAL COLORATIUX. 



Sexual Dimorphism in Colour. — Sexual Dimorphism of Colour most marked 

 in Birds and Butterflies. — Slight Development of Colour Dimorphism 

 in Mammals. — Dependence of Sexual Dimorphism from the Generat- 

 ing Laws. — The Theory of Sexual Selection. — Difficulty of Believing 

 in a highly-developed jEsthetic Sense. — ^Esthetic Sense of Butterflies. — 

 Objections to the Theory of Sexual Selection. — Excitabilitj' .it Breed- 

 ing Season of Animals among which there is no Pairing. — Some 

 arguments in favour of Sexual Selection. — The Courtship of Spiders. 

 - Sexual Dimorphism partly due to a Need for Protection on the 

 part of the Female.- -Mr. Stoltzmann's Views, — Mr. Wallace's Views. 

 — Summary ........ . 2:"io 



CiENKEAL InDJSX . . . 28.S 



Index of Author's Xamhs. . ... . L's7 



