CONTENTS xi 



CHAPTER XII 



PAGE 



Reproduction — Concerning Eggs -------- 195 



Number of eggs in a " clutch ", Shape of the egg. Size. Texture and 

 thickness of the shell. Colours of eggs. Origin of the colours. 

 Patterns of coloration. Colours of eggs in relation to classification. 

 Coloration in relation to environment. White eggs and their mean- 

 ing. Structure and composition of the egg. 



CHAPTER Xni 



Reproduction (continued) — Care of the Offspring .... 213 



Brooding and " brood-spots ". Care for the sitting female. The remark- 

 able case of the Hornbill. The brooding of the Emperor Penguin. 

 Brooding of Egyptian Plover and of Megapodes. Forsaking eggs. 

 Osprey and care of eggs. Transportation of eggs by parents. Pre- 

 cautions against floods. 



CHAPTER XIV 



Care of Offspring (continued) 223 



The care of the young undertaken by the male alone, and by the female 

 alone, or by both parents. The remarkable case of the Sand-grouse 

 in procuring water for their young. The strange case of the trans- 

 portation of the young in the Woodcock. Feeding customs. 

 Sanitation of the nest. The callousness of Eagles. The coloration 

 of nestlings. 



CHAPTER XV 



Nestling Birds and what thev Teach 235 



The differences between young birds and young reptiles. Nestling birds 

 and the systematists. The clothing of nestlings. Primitive nest- 

 lings. Precocious flight. Helpless nestlings. The coloration of 

 nestling birds and its significance. 



CHAPTER XVI 



The Life-history of Birds — an CEcological Summary - - - 262 



Embryology in outline. No hard-and-fast line between embryonic and 

 post-embryonic characters. Plumage phases. Some puzzling facts 

 with regard to adult characters. The plumage of Thrushes. Signs 

 of maturity. Nuptial liveries. Coloration and its evolution. Moult- 

 ing. Abrasion phenomena. The age of birds. Mortality. Play of 

 birds. 



CHAPTER XVII 



Variation : Continuous and Discontinuous — Inter-breeding - - 291 



Paucity of information on variation in birds. The work of J. A. Allen. 

 Relation of variation to natural selection. Barrington's work. 

 Colour variation. Dimorphism. Mutation. Albinism and Melan- 

 ism. Swallows. 



