4 EXTINCT AND VANISHING MAMMALS 



adopted here happens to be less familiar than one or more that are 

 replaced, the latter may be cited. Or, if certain recently proposed 

 names are not considered valid, these may likewise be cited in 

 synonymy. 



Persons interested in the study of mammals have frequent need 

 of consulting good illustrations of the various species and subspecies. 

 For this reason a special point has been made of supplying refer- 

 ences to such illustrations. While such a list of references can rarely 

 be exhaustive, it is believed that the hundreds of references given 

 here include at least a majority of the good published figures or 

 plates of the mammals under discussion. In the case of slightly 

 differentiated subspecies, an outstanding difficulty very frequently 

 encountered has been the determination of the particular one 

 figured. Even if the author or artist has provided a trinomial 

 designation and this is far from being a universal practice there 

 is always a possibility of misidentification, or of eventual refinement 

 of classification that will throw the identification into doubt, 

 unless the geographical provenance of the specimen figured is 

 accurately stated. The frequent disregard of this rule is the cause 

 of endless vexation, and it detracts seriously from the value of the 

 figures as zoological illustrations. Thus, in many cases the sub- 

 specific identity of a figure mentioned in the references is in doubt, 

 and some of these cases are indicated by a parenthetical query: 

 "subsp.?" This uncertainty of identification extends inevitably 

 even to some of Mr. Poole's excellent drawings that illustrate the 

 present text. For some are based upon "zoo" specimens, many of 

 which are notoriously of uncertain provenance or even represent the 

 hybrid offspring of different subspecies in captivity ; while others are 

 based upon previously published figures, themselves of somewhat 

 uncertain subspecific identity. 



A brief description of each species or subspecies is included. In 

 its preparation I have aimed to utilize the type description so far 

 as it is at all adequate; but in many cases later and more complete 

 or more accurate descriptions have necessarily been drawn upon 

 for at least some of the characters. Constant caution is required, 

 however, in making use of reviews, catalogues, or monographs in 

 which the descriptions may be based upon specimens of unspecified 

 provenance. In all possible cases I have indicated the source of the 

 information by a direct quotation or, in the case of translation or 

 paraphrasing, by at least a bibliographical reference. 



It may be remarked here that the entire report is documented 

 with such references to the fullest possible extent, not only as a 

 matter of simple justice to the authors of the works drawn upon, 

 but as an essential aid to the reader in verifying statements, and in 

 ascertaining what source material has been utilized on the one hand, 



