vi PREFACE. 
to Mr. Bailey’s untimely death and Mr. Mosher’s occupation 
in a new field, it was deemed best to publish some of the 
field notes of these observers with little editing, in order to 
avoid any possible distortion of their evidence. 
In presenting in Chapter I. some of the evidence, given by 
the earlier writers, regarding the utility of birds as protectors 
of crops and trees, it has been necessary to use such material 
as was obtainable. No carefully guarded experiments or 
observations in this direction were made until the latter part 
of the nineteenth century, and it is only recently that scien- 
tific investigators have been employed in this little-known 
field. It is not an alluring task for the scientist, in which 
his work brings him neither material reward, credit, nor 
honor. 
That portion of the final chapter which treats of the means 
of attracting birds is drawn mainly from six years’ experience 
at the author’s home at Wareham, Mass. The first three 
chapters were mainly written there. Most authors quoted 
or cited in these chapters are given full credit. 
The remaining chapters, which are largely based on the 
author’s own investigations and observations, were written 
and the proof was read while he was away from home, in the 
woods, or travelling from place to place, often at a distance 
from any ornithological library. Under such circumstances 
it was impossible to quote verbatim, but in most cases authors 
are named when facts have been gathered from their writings. 
The averages of the components of the food of each species 
are taken mainly from the publications of the Bureau of Bio- 
" logical Survey of the United States Department of Agricul- 
ture, except where credit is otherwise given. 
Thanks are due to Dr. L. O. Howard, who has read 
critically that part of the introduction devoted to insects, 
and the author is greatly indebted to him for information ; 
also, more than he can tell, to Mr. William Brewster for 
counsel and suggestions ; and especially to Mr. J. A. Farley, 
who read a large part of the manuscript. ° 
The limited time at the author’s disposal has prevented 
such painstaking revision and abridgment of the manuscript 
