X BULLETIN 191, UNITED STATES NATIONAL MUSEUM 



The plumages are described in only enough detail to enable the reader 

 to trace the sequence of molts and plumages from birth to maturity and 

 to recognize the birds in the different stages and at the different seasons. 



No attempt has been made to describe fully the adult plumages; 

 this has been well done already in the many manuals and State bird 

 books. Partial or complete albinism is liable to occur in almost any 

 species; for this reason, and because it is practically impossible to locate 

 all such cases, it has seemed best not to attempt to treat this subject at 

 all. The names of colors, when in quotation marks, are taken from 

 Ridgway's Color Standards and Color Nomenclature (1912). In the 

 measurements of eggs, the four extremes are printed in boldface type. 



Many who have contributed material for previous volumes have con- 

 tinued to cooperate. Receipt of material from nearly 500 contributors 

 has been acknowledged previously. In addition to these, our thanks 

 are due to the following new contributors: J. R. Arnold, B. W. Baker, 

 E. R. Blake, R. M. Bond, W. P. Bonney, F. W. Braund, N. R. Casillo, 

 A. D. Cruickshank, D. E. Davis, O. E. Devitt, P. F. Eckstorm, J. H. 

 Ennis, H. S. Gilbert, W. E. Griffee, J. G. Griggs, B. E. Harrell, C. F. 

 Holmes, J. S. Y. Hoyt, W. A. Kent, A. J. Kirn, J. M. Linsdale, W. H. 

 Longley, D. D. MacDavid, E. A. Mason, M. L. Miles, A. B. Miller, 



D. L. Newman, E. P. Odum, F. M. Packard, E. J. Reimann, A. C. 

 Reneau, Jr., H. G. Rodeck, W. F. Smith, M. Sullivan, W. P. Taylor, 

 J. K. Terres, Jr., H. O. Todd, Jr., B. W. Tucker, H. E. Tuttle, H. D. and 

 Ruth Wheeler, and J. B. Young. If any contributor fails to find his or her 

 name in this or in some previous Bulletin, the author would be glad 

 to be advised. As the demand for these volumes is much greater than 

 the supply, the names of those who have not contributed to the work 

 during the previous ten years will be dropped from the author's mailing 

 list. 



Dr. Winsor M. Tyler rendered valuable assistance by reading and 

 indexing, for these groups, a large part of the literature on North 

 American birds, and contributed two complete life histories. Dr. Jean 

 M. Linsdale and B. W. Tucker, of the Department of Zoology, Oxford 

 University, contributed two each ; and Edward von S. Dingle, Dr. 

 Alfred O. Gross, and Alexander Sprunt, Jr., contributed one each. 



Egg measurements were furnished, especially for this volume, by the 

 American Museum of Natural History, Griffing Bancroft, Herbert W. 

 Brandt, Frank W. Braund, California Academy of Sciences, Colorado 

 Museum of Natural History, Cl'.arles E. Doe, Field Museum of Natural 

 History, James R. Gillin, Wilson C. Hanna, Ed. N. Harrison, Turner 



E. McMullen, Museum of Comparative Zoology, Museum of Vertebrate 

 Zoology, Laurence Stevens, George H. Stuart, 3d, and United States 

 National Museum. 



