1914 



ACKNOWLEDGMENTS 



In going through literature dealing with the subject it became apparent that, 

 many of the older government reports, and some more modern works as well, 

 contained, among much trustworthy and valuable information, statements re- 

 garding certain species which needed corroborative proof other than that to be 

 found on the printed page. This was a phase of the problem utterly beyond the 

 author's power to deal with, unaided, and he is correspondingly grateful to Mr. 

 W. W. Cooke of the Biological Survey, for cordial assistance in supplying def- 

 inite information regarding many of these doubtful cases. Further acknowledg- 

 ment is made in the following pages in each of the rather numerous instances in 

 which his aid was invoked. 



To Professor C. B. Cory and Mr, W. H. Osgood, of the Field Museum of 

 Natural History, obligations are acknowledged for permission to print hitherto 

 unpublished data regarding certain specimens in the ornithological collection of 

 that institution. To Mr. F. C. Baker, of the Chicago Academy of Sciences, the 

 author expresses his gratitude for the free use of the library of the academy ac- 

 corded him, as well as for assistance and advice in the pursuit of the bibliograph- 

 ical portion of the work. 



To Mr. G. Frean Morcom grateful thanks are extended for his generous sup- 

 port of, and deep interest in, field work which otherwise could hardly have been 

 undertaken. From Mr. F. S. Daggett, now Director of the Los Angeles Museum 

 of History, Science, and Art, the author received advice and encouragement on 

 many occasions. Mr. Daggett added to his own collection large series of birds col- 

 lected at certain localities in y\rizona which the author had been unable to visit, or 

 which were taken at different seasons of the year from the time of the author's 

 work in the region, and the information gained thereby was freely placed at his 

 disposal. 



Mr. F. C. Willard, of Tombstone, Arizona, obligingly read the manuscript 

 of this list, with a view of adding thereto such unpublished records of his own, 

 obtained during a number of years of careful observation of the birds of south- 

 eastern Arizona, as would add to the statements made by the author. The valu- 

 able information thus secured is cited in the text as "F. C. Willard. MS"' 



Mr. A. B. Recknagel, Assistant District Forester. Albuquerque, New Mex- 

 ico, very kindly loaned the author blue print maps which were on file in nis of- 

 fice, illustrating the distribution in Arizona of seven conspicuous species of forest 

 trees, useful as zone indicators. The data thus obtained, of the greatest value in 

 compiling a map of the life zones of Arizona, could have been secured in no 

 other way, and the author is deeply appreciative of the courtesy extended him. 



Finally, grateful appreciation is hereby expressed for the co-operation of 

 Mr. Joseph Grinnell, whose assistance and advice have materially aided in the 

 completion of this list, and whose helpful suggestions throughout the course of the 

 undertaking have strongly influenced the author, both in regard to matters of 

 form and methods of work. 



H. S. SWARTH. 



Los Angeles, California, April t, ipT^^, 



