The technical, or descriptive, matter of the present work has been prepared by Messrs. Baird and Ridgway, that relating to the _Raptores_ entirely by Mr. Ridgway; and all the accounts of the habits of the species are from the pen of Dr. Brewer. In addition to the matter supplied by these gentlemen, Professor Theodore N. Gill has furnished that portion of the Introduction defining the class of birds as compared with the other vertebrates; while to Dr. Coues is to be given the entire credit for the pages embracing the tables of the Orders and Families, as well as for the Glossary beginning on page 535 of Vol. III. Nearly all the drawings of the full-length figures of birds contained in the work were made directly on the wood, by Mr. Edwin L. Sheppard, of Philadelphia, from original sketches taken from nature; while the heads were executed for the most part by Mr. Henry W. Elliott and Mr. Ridgway. Both series have been engraved by Mr. Hobart H. Nichols of Washington. The generic outlines were drawn by Anton L. Schönborn, and engraved by the peculiar process of Jewett, Chandler, & Co., of Buffalo. All of these, it is believed, speak for themselves, and require no other commendation. A considerable portion of the illustrations were prepared, by the persons mentioned above, for the Reports of the Geological Survey of California, and published in the volume on Ornithology. To Professor Whitney, Chief of the Survey, acknowledgments are due for the privilege of including many of them in the present History of North American Birds, and also for the Explanation of Terms, page 526 of Vol. III. A few cuts, drawn by Wolf and engraved by Whymper, first published in “British Birds in their Haunts,” and credited in their proper places, were kindly furnished by the London Society for the Diffusion of Christian Knowledge; and some others prepared for an unpublished volume by Dr. Blasius, on the Birds of Germany, were obtained from Messrs. Vieweg and Son, of Braunschweig. The volume on the Water Birds is in an advanced state of preparation, and will be published with the least possible delay. SPENCER F. BAIRD. SMITHSONIAN INSTITUTION, WASHINGTON, January 8, 1874. CONTENTS. Page PREFACE v INTRODUCTION xi