PREFACE TO THE FOURTH EDITION. 
1 presenting a new edition of the Key to those who are interested in North 
American Birds, the publishers desire the author to add a word by way 
of preface. But little need be said of a book which speaks for itself in passing 
through several editions to supply that demand for a standard textbook of 
ornithology which this work has itself done much to create, by stimulating and 
satisfying an interest in one of the most delightful departments of Natural 
History. 
The part which the Key has taken in the evolution of the subject since 
1872 is sketched in the “Historical Preface” (pp. xxvi-xxx), first introduced 
in the Second Edition, 1884. Since the founding of the American Ornitholo- 
gists’ Union in 1883 the impetus then given to the study of birds has resulted 
in a momentum directly proportionate to the number of workers in this field 
and to the length of time these have been engaged. I could wish the fruits 
of such unparalleled activity were all sound and ripe, but they are not; growth 
has been forced to some extent in rival hot-houses, and the familiar parable of 
wheat and tares finds a fresh illustration. Too quick transition from an old to 
a new order of things in the technicalities of our subject has brought disorder, 
as usual. Till the pace slackens somewhat, so that we can see where we stand, 
I do not think it would be wise to recast the Kry. | 
Therefore, the only change in the present edition is the addition of a Second 
Appendix, beginning page 897. 
E. C. 
