TAP.LE OF CONTENTS. 



Page. 



Letter of transmittal 13 



Introductory letter, by Dr. H. C. Yarrow, Acting Assistant Surgeon, U. S. A., Surgeon 



and Zoologist 15 



Chapter I. — Notes upon geographical distribution and variation with regard to the 

 zoology of the Western United States, as relates more particularly to 

 Mammals and Birds, by Dr. IT. C. Yarrow 23 



Chapter II.— Report upon the collections of Mammals made in portions of Nevada, Utah, 

 California, Colorado, New Mexico, and Arizona during the years 1871, 

 1872, 1873, and 1874, by Dr. Elliott Coues and Dr. H. C. Yarrow 3u 



