CONTENTS vii 



CHAPTER VIII 



The senses of birds Sight and its general high development 

 Degree of perception of colour Influence of colour, if any, 

 on courtship, and the segregation of species Perception of 

 the colour in various kinds of food Smell, usually poorly 

 developed Exceptions noted Acuteness of hearing Sense 

 of touch Taste-perceptions . . . pp. 225-254 



CHAPTER IX 



The emotions of birds Mentality higher than is supposed, but 

 variable according to species or groups Strong- and weak- 

 minded birds Intelligence and stupidity The limitations 

 of instinct Expression of the emotions and its relation to 

 courting displays Love and sociability Hatred and re- 

 venge The police instinct Monogamy, polygamy, and 

 polyandry The problem of preferential mating pp. 255-280 



CHAPTER X 



Song and cries of birds Bird-language generally Extent to 

 which the notes are instinctively developed The instinct of 

 mimicry Species which can imitate human speech Problem 

 of this ability and extent of exercise of the same Possibility 

 of understanding of bird-language by man . pp. 281-292 



CHAPTER XI 



Weapons and fighting methods of birds Their combats with 

 each other and with various natural enemies Chief enemies 

 of birds The passive resistance of birds to unfavourable 

 climate and surroundings Natural defences Perfection and 

 degeneracy of plumage in this connection Powder-coating of 

 some groups pp. 293-302 



