2 PROCEEDINGS : BOSTON SOCIETY NATURAL HISTORY. 



of the study of North Araerican land mammals to the close of the 

 year 1900, and to furnish an index to the literature of the subject 

 for the past fifteen years. It is not an expression of individual 

 opinion ; and no i-evisionary work has entered into its preparation. 

 North America, as here understood, is the entire^ Amerit^an continent 

 north of a line drawn across the Isthmus of Panama from Colon to 

 the City of Panama, together with Greenland, and those islands of 

 the West Indies the fauna of which is not pureh' South Araerican 

 in its affinities. 



In 1885^ Mr. F. W. True published 'A provisional list of the 

 mammals of North and Central America and the West Indian 

 Islands,' a summary of the North American mammal fauna as 

 then known. To the species included in it are here added those 

 since recognized, the status of which at the end of the year 1900 

 had not been questioned in some recent work of definite mono- 

 graphic character, where full synonymy and references may readily 

 be consulted. Forms in regard to whose standing there is differ- 

 ence of opinion, but which have not been treate<l in such a mono- 

 graphic paper, are included ; but in cases of this kind references are 

 given to the conflicting views. The sequence of groups is essen- 

 tially that of Trouessart's ' Catalogus niammalium tam viventium 

 quam fossiliutn ' (Berlin, 1897-1899) with the order reversed to con- 

 form with the }>revalent oi)inion that eniimeration should begin with 

 the more generalized types rather than with the more specialized. 

 The arrangement of s})ecies is alphabetic except in the case of 

 genera that have been recently monographed ; here the sequence 

 adopted by the reviser is followed, and any additions made subse- 

 quently to the publication of the revision are entered in accord- 

 ance with their supposed affinities. Under every species and sub- 

 species reference is made to the first publication of the specific or 

 subspecific name. To this, when necessary, is added (a) reference to 

 first use of current binomial or trinomial name, (b) in the case of 

 species described before 1885, but not at that date admitted as 

 valid, reference to establishment as members of the North .Vmeri- 

 can fauna, and (c) reference to True's list.'-^ The species included by 



1 Proceedings of the United States National Museum, VII (1884), pp. 587-611 (ai)pen- 

 dix). 1885. 



2 No attempt is made in the case of tlie many species which prove to have been com- 

 posite, as understood in 1885, to apportion the name tlien used to eacli of the component 

 parts as they now stand. The word ' part ' in parentheses after the reference indicates 

 that segregation has taken place. 



