INTRODUCTION 
XXV11 
Naturalist collectors are far from being the ruthless destroyers of 
life they are often supposed to be. It is, indeed, those who collect 
the birds, study them most deeply, and know them best, who are 
doing the most for their protection. Most ornithologists have begun 
their study of birds by making private collections, and have turned 
the knowledge thus gained to the best good of the birds, while their 
collections have finally gone to museums, where they could benefit 
the greatest number of students. 
In most museums, it is true, there are large collections of bird 
skins, often hundreds of specimens of a single species, showing 
every shade of variation due to age, sex, season, moult, and wear of 
plumage, and endless geographic variation over a wide range of 
country; but to many of those who have the best chance to study 
the birds in life these collections are inaccessible. 
There are still unknown, rare, and little known species of birds 
that must be obtained before our knowledge of our own species can 
be approximately complete and our system of classification firmly 
established. But the more immediate and pressing question before 
the young ornithologist is how to identify the obscure species and 
the females and young of better known birds. In many cases the 
bird must be shot to be identified, and not infrequently it must be 
sent to some large museum collection for comparison for satisfactory 
determination. Collecting, therefore, has not only a legitimate but 
fundamental place in ornithology as a scientific study. 
Measurements. — It should be borne in mind that measurements 
are not infallible, and even where the maximum and minimum of a 
seiies are given, still larger or smaller specimens may be found. 
In many cases measurements are useless in determining characters, 
but in others they are the all important differences between species 
and subspecies. The total length is the most variable measurement, 
and when taken from a skin instead of a bird in the flesh is only 
intended to give a general idea of the size of the bird. In quoting 
Mr. Ridgway’s measurements throughout this book the word 
‘ about * has been omitted from his lengths, as it applies to all length 
measurements. Lengths are taken from the birds in the flesh, if not 
specifically stated to be from skins. All measurements in the book 
are in inches. Wing, tail, bill, and tarsus measurements are the 
important ones in most species, especially so because they can be 
taken from the dry skin as well as from the fresh specimens. Mea¬ 
surements should be taken in the following manner: — 
Length. — From tip of bill to tip of tail. To get this lay the 
