222 PROCEEDINGS OF THE NATIONAL MUSEUM vol.83 



of the whole fauna, but this hope was still unfulfilled at the time of his 

 death in 1931. In 1932, Dr. Alexander Wetmore and C. W. Gilmore, 

 of the National Museum, invited me to carry out Dr. Gidley's plan 

 and to write the proposed memoir, an invitation gratefully accepted 

 as an opportunity for useful work and for a most fitting and practical 

 tribute to the memory of a friend and colleague. The American 

 Museum has permitted the use of my time as a cooperative under- 

 taking with the National Museum. 



This study and the even slower preparation of the illustrations are 

 now well advanced, but it will be at least a year and possibly several 

 before it can be published. In the meantime, it seems necessary to 

 facilitate the work of others and the study of the Paleocene in general 

 by publishing names and brief diagnoses of the new genera and species 

 so far recognized. Those studied are here published, and possibly 

 some others may appear in similar preliminary form before the entire 

 memoir is published. Full descriptions, discussions of affinities, and 

 illustrations will appear in the memoir. 



Aside from a few records and notes for his published papers. Dr. 

 Gidley left 27 sheets of manuscript in various stages of preparation, 

 in part duplicated or different drafts of the same subject. These 

 limited notes were evidently prepared over a long period, all some 

 time ago, and they probably do not express Dr. Gidlej^'s definitive 

 opinions. In studying the collection, I have first examined the speci- 

 mens independently and then have ascertained whether new genera 

 or species recognized by me are named and defined in Gidley's notes. 

 In several cases they are (and in these instances I publish the names 

 as of Gidley, ex ms., quoting his diagnosis and, if necessary, following 

 it by an emended diagnosis by me). This will, I hope, make the work 

 unified and abreast of recent knowledge, and at the same time will 

 give Dr. Gidley proper credit for the discoveries that he had reduced 

 to paper. In a few other cases there are notations on labels that 

 specimens represent new species, but with no manuscript name or 

 diagnosis. Of these (so far as I agree that the species are new) I am 

 forced to assume authorship, but I also record their recognition by 

 Dr. Gidley. 



Following is a list of the mammals so far recognized in the Fort 

 Union of the Crazy Mountain Field. It includes 40 genera (15 new 

 herein) and 57 species (37 new). Even this large list does not fully 

 represent the variet}'- actually present, for there are numerous species 

 not yet adequately studied. Most of the listed mammals are from 

 the Gidley and Silberling Quarries, but some are from markedly 

 different levels, although all appear to be Middle Paleocene. Exact 

 distributional data are available and will be published later. 



