PREFACE xi 



The pleasantest part of preparing the narrative has 

 been the co-operation of my wife. 



A legitimate number of the animals killed were re- 

 served for trophies; the others were collected especially 

 for the U. S. Biological Survey, and are now in the new 

 National Museum at Washington. 



The Biological Survey, a bureau of our National De- 

 partment of Agriculture, is an institution too little known, 

 and since it co-operated with me in all my work in the 

 north, thus adding pleasure not anticipated, I would 

 gladly bring its magnificent work to the attention of a 

 wider public than that of the specialists and others 

 directly interested. It was organized in 1885 for the pur- 

 pose of studying the food habits of our native birds and 

 mammals in their relations to agriculture, by Dr. C. Hart 

 Merriam, who possesses one of the keenest scientific 

 minds which the country has produced. Dr. Merriam 

 saw that the continent of North America, stretching from 

 the tropics to the Polar Sea, comprising vast areas of 

 tropical, temperate, and arctic lands, and supporting a 

 number of widely different fauna and flora, afforded 

 an unrivalled field for the study of the interrelations of 

 species, and the correlation of the distribution of animal 

 and plant life. He was the first to appreciate and demon- 

 strate the intimate relation between the agricultural pos- 

 sibilities of a region and the distribution of its native 

 forms of life. 



In order to learn the facts of distribution it was neces- 

 sary to collect and determine the species inhabiting all 

 parts of the continent. For this purpose trained natural- 

 ists were sent into the field to discover the boundary lines 

 of the various fauna, and to bring back collections for 

 critical study. During the past twenty years, nearly one 

 hundred thousand specimens of mammals, besides many 



