CHAPTER XV 



DISTRIBUTION OF MARSUPIALS AND 

 MONOTREMES 



Section I. — Introductory Remarks 



The distribution of the two lowest orders of mammals, at 

 which we have now arrived, is a comparatively simple 

 matter, as these primitive creatures, which, according to the 

 views of the highest authorities, form two primary sub- 

 classes of the whole class of Mammals (Metatheria and 

 Prototheria), are confined exclusively to two of the great 

 Zoological Regions of the earth. We will, nevertheless, 

 pass the different families and the principal genera of these 

 two orders in short review, and endeavour to point out the 

 principal known facts of their distribution. 



Section II. — Distribution of the Marsupials 



The Marsupials have, until recently, been classified in 

 six families, five of which belong to the Australian and one 

 only to the Neotropical Region, and such was the plan of 

 arrangement adopted for them by Mr. Thomas in his 

 excellent catalogue of this group of mammals published in 

 1888. But great discoveries in this class have been made 

 during the past ten years. A new Marsupial, of a most 



