76 TRANSACTIONS OF THE [ FEB. 23, 
of North American Rodentia.” While the two authors shared 
the labor about equally, the joint authorship implied in the 
title relates merely to the fact that their separate memoirs 
are bound together under one general title, the different mono- 
graphs being each by a single author. ‘The work consists of 
eleven separate and distinct memoirs. In two cases, as in the 
monographs of the squirrels and hares, the scope is greater 
than is indicated by the general title of the work, all of the 
species found in Mexico, South and Central America, being 
included, as well as those from North America. An important 
feature of this work is the bibliographical appendix, by Gill 
and Coues, consisting of about 130 pages, and bringing. the 
bibliography of North American mammals down to the year 
1874, in a very thorough manner, and including most of the 
titles down to as late as 1876." 
In 1880 I published an octavo volume of about 800 pages, with 
numerous illustrations in the text, entitled ‘‘ History of North 
American Pinnipeds: a Monograph of the Walruses, Sea- Lions, 
Sea-Bears, und Seals of North America,” treating the subject 
at length in all its bearings. 
In addition to the special works already enumerated, number- 
less papers, some of them of great importance, have appeared in 
Government reports and in the transactions of scientific societies. 
Some of these are simply more or less fully annotated faunal 
lists; others are faunal lists, including incidentally much tech- 
nical matter ; others are more or less elaborate monographs of 
particular genera or families; others still are brief papers de- 
scribing new species or recording rare ones. Baird published 
practically nothing on mammals after 1859, since which time 
the most prominent names in the field have been Harrison 
Allen, J. A. Allen, Caton, Cooper, Cope, Coues, Dall, Gill, 
Kennicott, Mearns, Merriam, Scammon, and True. 
Besides these, Alston, of England, has published on the 
mammals of Mexico, in Godman and Salvin’s ‘‘ Biologia Centrali- 
Americana”; De Saussure has also written important papers on 
the same subject; while Brown and Ross have published valu- 
able memoirs on the mammals of Arctic America. 
'The titles of works and papers briefly mentioned in the present 
paper will be found there given in full. The intended scope of the 
work was to include ‘‘(a) all works and papers on mammalia at large 
published in North America, (b) all works and papers, wherever pub- 
lished, relating to North American mammals, and (c) such general 
works or collateral special papers as bear more or less directly upon 
the subject.” The titles are arranged chronologically under a few 
general heads. Though not put forth as absolutely complete, it still 
remains the most extended compilation on the subject yet published. 
