Preface ix 
In my treatment of the various phases of the bird’s 
physical life I have been considerably influenced by the 
many questions which I have heard asked by visitors to 
the New York Zoological Park. The short list of books 
in the Appendix will indicate the sources whence much 
more detailed information may be obtained by those who 
desire it. 
Some two dozen of the illustrations are from outside 
sources, and for permission to use these I am indebted 
to Dr. William T. Hornaday, the American Museum 
of Natural History, Prof. A. Smith-Woodward, Prof. R. 
8. Lull, A. E. Brown, Esq., Mr. R. H. Beebe, Mr. T. H. 
Jackson, Mr. Harold Whealton, and Mr. E. H. Baynes; 
and for the use of specimens to Dr. F. A. Lucas, Dr. 
Robert Ridgway, and Dr. Jonathan Dwight, Jr. Unless 
otherwise indicated, the illustrations were taken by the 
author. 
The work of Mr. Walter King Stone in the paint- 
ing for the frontispiece and a number of text cuts is 
gratefully acknowledged; and for the skilful printing of 
many of the photographs my thanks are due to Mr. E. 
R. Sanborn. 
To my wife, for constant and valuable help, criticism, 
and suggestion in all departments of the book, I render 
my sincere appreciation. 
To take a few dead facts and clothe them with the 
living interest which will make them memorable and full 
of meaning to any lover of birds, and at the same time 
to keep them acceptable in tenor and truth to the most 
critical scientist—this has been my aim. 
