PEEFACE TO THE FIFTH EDITION. lU 



In the nomenclature and classification of the Birds, I 

 have followed exactly the " Check List of North Ameri- 

 can Birds," published by the American Ornithologists' 

 Union. In the preparation of analytical keys to the 

 genera of Birds, I have made large use of Ridgway's 

 " Manual of North American Birds," and of Coues' " Key 

 to North American Birds." In the arrangement of the 

 Mammals, I have been guided primarily by Professor 

 Baird's " History of North American Mammals." In the 

 Rodentia, I have made use of the elaborate monographs of 

 Dr. Elliott Coues and Dr. J. A. Allen ; and in the other 

 groups reviewed by Dr. Coues, I have adopted most of 

 his conclusions. In the Cetaceans, I have used chiefly 

 the papers of Mr. Frederick W. True and Prof. E. D. 

 Cope, and both these naturalists have kindly furnished me 

 with unpublished catalogues of the species recognized by 

 them. 



In the preparation of the present edition I am also 

 personally indebted for aid in various ways to Prof. Ed- 

 ward D. Cope, Mr. Leonhard Stejneger, Prof. Charles H. 

 Gilbert, Prof. Oliver P. Hay, Mr. Frederick W. True, Mr. 

 Robert Ridgway, Mr. Amos W. Butler, Dr. J. Sterling 

 Kingsley, Mr. Charles H. Bollman, Dr. Stephen A. Forbes, 

 Mr. Barton W. Evermann, and others. I may again refer 

 to the obligations acknowledged in the earlier edition, — 

 especially to my indebtedness to Dr. Elliott Coues, Dr. 

 Theodore Gill, Dr. G. Brown Goode, Dr. Tarleton H. Bean, 

 Prof. Herbert E. Copelaud, and Mr. Edward W. Nelson. 



DAVID S. JORDAN. 



Bloomington, Indiana, 



June, 1888. 



