PREFACE 



THE WARBLERS have been described as "our most beautiful, 

 most abundant, and least known birds." The knowledge that 

 at certain seasons our woods, and even the trees of our larger 

 city parks are thronged with an innumerable host of birds, the bril- 

 liancy of whose plumage rivals that of many tropical species, comes to 

 the bird student with the force of a surprising discovery. One never 

 forgets one's first Warbler ! 



Highly migratory, the extended journeys of Warblers are never- 

 theless performed with regularity which makes their appearance in 

 the spring a fixed calendar event. The very essence of the season 

 is in their flitting forms and lisping voices ; without them May would 

 seem a dreary month and the migration of birds lose half its charm. 



But these dainty, fascinating sprites of the tree-tops are elusive. 

 Years of observation may be required to add to one's list of field 

 acquaintances the last of the thirty-odd species which, in eastern 

 North America, may be found at a single locality. 



In this quest the field-glass student is handicapped. The small 

 size of Warblers, their activity, the nature of their haunts, their rapid 

 journeys, marked seasonal changes in plumage, and the general resem- 

 blance in the song of many species all tend to render recognition in life 

 unusually difficult. This book has, therefore, been prepared with the 

 cooperation of other ornithologists, to meet the demand for a fully 

 illustrated work which will serve as an aid to the field identification of 

 Warblers and to the study of their life-histories. 



F. M. C. 



American Museum of Natural History, 

 New York City, January, 1907. 



