PLAN OF THE WORK 
Introduction . — The Introduction to the present edition of the 
“Handbook” is wholly new, and is designed to meet the wants of a 
class of bird-students which was almost unknown when the first edition 
of the “Handbook” was written. Field work in eastern North America 
then meant chiefly collecting. Now it means chiefly observing. The 
observation blind, the camera, the note-book to record prolonged, con- 
secutive, definitely directed studies, were then used rarely, if at all. 
Now they form part of the equipment of all serious students of birds 
in nature, and it is to them that this Introduction is addressed. 
Nomenclature.— The nomenclature of the American Ornithologists’ 
Union’s “Check-List of North American Birds” (third edition, 1910) has 
been adopted. The number preceding the name of each species is its 
permanent number in the Union’s “Check-List.” 
Through an oversight, trinomials were not employed in the “Check- 
List” for certain races, of which only the one first described occurs in 
North America, and such species are here entered under their proper 
trinomial designation. 
I have not, however, followed this plan for species of wholly acci- 
dental occurrence, with which a re-examination of the specimen or 
specimens on which the records are based might be essential to their 
correct subspecific determination. 
With the object of encouraging uniformity in the use of common or 
vernacular names of our birds, I have given in the body of the book 
only one such name for each species — that adopted for it in the “Check- 
List” of the American Ornithologists’ Union. Other common names, 
which have been or are in more or less general use, are given in the 
index, with a cross reference to the name with which they are syn- 
onymous. 
In some instances, I have taken the common names of the earlier, 
rather than of the last, edition of the “Check-List,” in which abbre- 
viations have been made with consequent loss of definiteness. Exam- 
ples are “Scaup,” “Scoter,” “Crossbill,” and other instances where two or 
more species, having the same general name, are found in the same 
locality. In such cases, it is evident that, to avoid ambiguity, each one 
should have some qualifying title. 
Definition of Terms. — The accompanying figure, with its named 
parts, will explain the meaning of the terms used in the following 
descriptions of birds. The words upperparts and underparts, mentioned 
so frequently, refer respectively to the whole upper or under surfaces 
of the body of the bird, from the base of the bill to the root of the tail, 
but are not applied to either wings or tail. 
(xiii) 
