﻿INTRODUCTION. 



In few, if in any group of Mammals, is our knowledge of spe- 

 cies and genera in such a satisfactory condition as is the case 

 with the Marsupials and Monotremt-s. This is entirely due to 

 the labours of Mr. Oldfield Thomas, of the British Museum, 

 whose results are published in the " Catalogue '' so often re- 

 ferred to in the course of the following pages. 



Under such circumstances, the task of writing a jjopular 

 monograph of the groups in question has been a comparatively 

 easy one ; and the present volume must be regarded as little 

 more than an abridgment of Mr. Thomas's work put into a 

 more popular guise, with the omission of certain osteological 

 and other more technical details. Since the publication of 

 his "Catalogue" in 1888, a few new species have been dis- 

 covered or described, which are inserted in their proper places 

 in this book, by far the most interesting of these being the 

 Marsupial Mole, representing a type of the Order previously 

 quite unknown. Moreover, since the past history of the 

 Marsupials has an important bearing on their present very 

 restricted geographical distribution, it has been felt that no 

 treatise on the group would be complete without some refer- 

 ence to this subject. Accordingly, a sectioii of the work has 

 been devoted to the consideration of some of the more gener- 

 ally interesting extinct representatives of that Order, while it 



