INTRODUCTION. 



The present work on the Eggs of North American Birds em- 

 bodies the results of my studies on this subject during the 

 past thirty years. During this time, m;iuy thousand speci- 

 mens have been examined and notes made on them. Besides 

 this, I have, when necessary, supplemented my own observa- 

 tions with those of others, and have consulted all available 

 works upon the subject for this purpose. But, unless so 

 stated, I am responsible for the descriptions. 



I have deemed it quite unnecessary tO' repeat descriptions of 

 the eggs of allied species where the differences in the average 

 specimens are indistinguishable, but have simply stated this 

 fact. All of the names of the species and sub-species of birds 

 wliich occur within the prescribed limits are included in the 

 work ; and, CA-en if their eggs are unknown, the bi-eeding ran<re, 

 when known, is given. No eggs are described unless the iden- 

 tification of the specimen is absolutely correct. 



In the matter of nomenclature, I have followed that of the 

 American Ornithologists' Union,- hoping thereby to secure un- 

 changing uniformity of names,. WMI^,. the boundary lines estab- 

 lished by that body are also used as defining the limits of the 

 North American avifauna. I have, however, made a few minor 

 changes, where I have personally dififered in opinion as to the 

 specific or sub-specific rank of certain birds. The changes, 

 however, are few and unimportant, as I have not considered a 



