PREFACE TO THE THIRD EDITION. 
HE second edition of the “Key,” which appeared in May, 1884, has al- 
ready been out of print for more than a year. Though aware of the 
continued demand for a standard work of reference, the author has been unable 
to meet it more promptly, having meanwhile accepted some other literary en- 
gagements which proved imperative in their demand upon his capacity for work. 
Slight as the requisite revision of this book has proven to be, it did not seem ex- 
pedient to go to press again without recognizing the steps American Ornithology 
has taken during the past three years, though these may be called many rather 
than great ones. There is so little to change in the substance of the book that 
it has been thought decidedly best to reprint from the same plates, and put what 
new matter has come to hand in the form of an Appendix. However much 
there is that might have advantageously gone into the second edition, but did 
not, the author is satisfied with nearly everything that did go in, and quite ready 
to submit it all to the still further test of time. The transition from what some 
of his friends have called the “Couesian Period” may mean a change in form 
rather than in fact. 
. The naming of our birds, as an art distinguished from the science of know- 
ing them, has lately been pitched in a key so high that the familiar notes of the 
former “Key” might jangle out of tune, or be lost entirely, were the attempt 
made to reset them just now. During the confusion unavoidably incident to 
such sweeping changes in nomenclature as we have recently made, it will be a 
decided benefit to the student, the sportsman, and the amateur, if not also to 
every working ornithologist, to be provided with a convenient means of compar- 
ing the older with the newer style of nomenclature we have adopted, until each 
one shall have grown accustomed to the change of spectacles. This accommoda- 
tion is afforded by the present edition, which leaves the names and their num- 
