PREFACE 



MY aim in writing this book is to present the study of 

 Bird Life from the point of view of the Evolutionist ; 

 to set forth, in broad outline, the evidence now 

 generally regarded as bearing on that most fascinating pro- 

 blem, the birth and growth of the various types of birds — 

 whether regarded as large groups, or as geographical races. 



The external beauty of form and colour which birds pre- 

 sent, has so far proved a serious distraction, so that Ornitho- 

 logists, captivated thereby, have paid but little heed to the 

 possible factors to which these features are due. At any rate, 

 since the master mind of Darwin himself laid the foundation 

 for this wider study of Bird Life but little progress has been 

 made. It is hoped, however, that this volume will prove a 

 stimulus to renewed efforts to penetrate some, at least, of the 

 many mysteries to which he called attention. 



The purpose of this book, then, is obviously to present the 

 Study of Birds as one of living organisms, moulded in part by 

 an inherent constitution, and in part by that " struggle for 

 existence " which is the lot of every living thing — a struggle 

 with environment, animate and inanimate. This being so, it is 

 obvious that anything more than the barest account of ana- 

 tomical details would be out of place here. True, these 

 "anatomical details" are the essence of the whole matter, but 

 though this be so their bearing on the question at issue, at 

 present, is not measurable ; and accordingly those who seek in 

 these pages for information of this kind will seek in vain. 



My expert critics will doubtless discover many omissions in 

 this book. I am aware of many : but I have had perforce to 

 select, and I have chosen those facts which seemed best to 



