VIII BULLETIN 17 0, UNITED STATES NATIONAL MUSEUM 



terms used to describe the shapes of eggs are taken from his Nomen- 

 clature of Colors (1886). In the measurements of eggs the four 

 extremes are printed in boldface type. 



Many of those who contributed material for previous bulletins have 

 continued to cooperate. Receipt of material from nearly 400 contrib- 

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

 thanks are due to the following new contributors: R. P. Allen, E. R. 

 and M. L. Arnold, D. B. Bull, A. W. Butler, C. H. D. Clarke, 

 Crompton Crook, J. A. Hagar, S. D. Knox, K. H. Maslowski, Theed 

 Pearse, R. W. Quillin, H. H. Schroder, E. T. Stuart, Jr., M. G. 

 Vaiden, F. C. Walcott, and Mrs. F. C. Willard. An attempt has 

 been made to record the names of all contributors, but omissions may 

 have occurred ; if any contributor fails to find his name, either in this 

 or in some previous bulletin, the author will be glad to be advised. 



Dr. Charles W. Townsend and Dr. Winsor M. Tyler rendered 

 valuable assistance in reading and indexing, for this group, a large 

 part of the literature on North American birds, which saved the 

 author many hours of tedious work. Dr. Townsend also contributed 

 the entire life histories of two species, and Dr. Tyler contributed one. 

 The Rev. Francis C. R. Jourdain contributed the life histories of three 

 European species, and Milton P. Skinner wrote those of nine North 

 American forms. Thanks are due also to the late Owen Durfee for 

 many hours of careful work in copying and arranging a great mass of 

 data on egg dates, and to F. Seymour Hersey for figuring egg measure- 

 ments. Egg measurements were furnished, especially for this volume, 

 by Griffing Bancroft, R. M. Barnes, C. E. Doe, J. R. Gillin, A. D. 

 Henderson, T. E. McMuUen, S. B. Peyton, J. H. Riley, J. S. Rowley, 

 W. B. Savary, G. H. Stuart, 3d, J. E. Thayer, Stanton Warburton, 

 Jr., and Miss M. W. Wythe. 



Through the courtesy of the Bureau of Biological Survey, the 

 services of Frederick C. Lincoln were again obtained to compile the 

 distribution paragraphs. With the matchless reference files of the 

 Biological Survey at his disposal, his many hours of careful and 

 thorough work have produced results far more satisfactory than could 

 have been attained by the author, who claims no credit and assumes 

 no responsibility for this part of the work. 



The manuscript for this volume was completed in April 1937. 

 Contributions received since then will be acknowledged later. Only 

 information of great importance could be added. The reader is 

 reminded again that this is a cooperative work; if he fails to find in 

 these volumes anything that he knows about the birds, he can blame 

 himself for not having sent the information to 



The Author. 



