xc 
INTRODUCTION 
Read down this as before, when, by throwing out the families to 
which it does not belong, you come to Ardeidm — 2'. Bill straight 
and sharp, neck and most of head feathered, to which it does belong. 
Go now to the page specified (72), and run down the Key to Genera, 
contained in Family Ardeidae, and you find that it belongs to the 
'genus Ardea, to which you are referred (p. 74). Here you find the 
general characters of the genus and a key to its species. As you 
know the bird is bluish gray and its size large you find it to be Ardea 
herodias, of which a detailed description is given (p. 75). If you 
have been identifying a bird that you have shot, you will have your 
own fresh measurements to compare with those in the description 
(see page xxvii.). 
In some of the more obscure birds you will find on getting to the 
description of the species that you have made a mistake in running 
down the keys, but by patience and care in following them you will 
be able to identify all but the most difficult birds. 
After a little study you will grasp the general classification of 
birds so that it will not be necessary to go through the whole series 
of keys for each bird. You may not know what it is, but you 
know many things that it is not, and if you make a practice of 
eliminating you will narrow down the possibilities so that it will be 
much easier to find your bird. You may not know whether it 
is a crow or a raven, but you do know that it is not a water bird, 
a hawk, owl, or sparrow, and so you can go on throwing out what 
you know it is not until you have to look up only those about which 
you feel uncertain. 
The question as to which subspecies a bird belongs to, unless de¬ 
terminable by geographic range, can often be decided only by expert 
ornithologists with large series of skins for comparison, and, in such 
cases, found often among some of the flycatchers, the song spar¬ 
rows, and wrens, the only way to be sure of your bird is to send it 
to a museum for identification. The National Museum in Washing¬ 
ton and the American Museum of Natural History in New York will 
both identify material sent them. 
