CONTENTS 



PART H. 



SEXUAL SELECTION'— continued. 

 CHAPTER XII. 



SECONDARY SEXUAL CHARACTERS OP FISHES, AMPHIBIANS, AND REPTILES. 



Fishes : Courtship and Battles of the Males. — Larger Size of the Females. — 

 Males, Bright Colors and Ornamental Appendages ; other Strange 

 Characters. — Colors and Appendages acquired by the Males during the 

 Breeding-season alone. — Fishes with both Sexes brilliantly colored. — 

 Protective Colors. — The less Conspicuous Colors of the Female cannot 

 be accounted for on the Principle of Protection. — Male Fishes building 

 Nests, and taking Charge of the Ova and Young. Amphibians : Differ- 

 ences in Structure and Color between the Sexes. — Vocal Organs. Rep- 

 tiles : Chelonians. — Crocodiles. — Snakes, Colors in some Cases pro- 

 tective. — Lizards, Battles of. — Ornamental Appendages. — Strange Dif- 

 ferences in Structure between the Sexes. — Colors. — Sexual Differences 

 almost as great as with Birds . . . . . p. 1 



CHAPTER XIH. 



SECONDARY SEXUAL CHARACTERS OF BIRDS. 



Sexual Differences. — Law of Battle. — Special Weapons. — Vocal Organs. — 

 Instrumental Music. — Love- Antics and Dances.— Decorations, Perma- 

 nent and Seasonal. — Double and Single Annual Moults. — Display of 

 Ornaments by the Males ...... 36 



CHAPTER XIV. 



birds — continued. 



Clioice exerted by the Female. — Length of Courtship. — Unpaired Birds. — 

 Mental Qualities and Taste for the Beautiful. — Preference or Antip- 

 athy shown by the Female for Particular Males. — Variability of 



