JERBOA POUCHED-MOUSE. 



CHAPTER I 



Australian and Tasmanian Animals 



Taken as a whole, the fauna of Australia and Tasmania differs so remarkably and 

 essentially from that of the whole of the rest of the world that there can be no 

 hesitation in regarding these islands as the typical representatives of a distinct 

 zoological realm — the Notogsea of geographical zoology — the nearest affinities of 

 which, if extinct forms be taken into consideration, appears to be with the South 

 American realm, or Neogaea. That New Guinea, or Papua, although it contains 

 animals more nearly related to those of Asia, should be included in the same 

 realm, is beyond doubt. The difficulty is where to draw the line separating the 

 Australian realm from the Oriental or Indian region, forming the most eastern 

 portion of Arctogsea, the realm including all the countries of the world not 

 comprised in either Notogsea or Neogsea. 



In the original scheme of geographical zoology, as formulated by Messrs. 

 Sclater and Wallace, the pioneers in this branch of science, the island of Celebes 

 and the smaller islands of Timor and Flores were included in the Australasian 

 realm, or region, the western boundary of which was drawn between Celebes and 

 the smaller adjacent island of Lombok. The channel dividing these two islands 

 was then believed to be of unusual depth ; and this eastern limit of the Australian 

 realm became universally known as " Wallace's line." Later researches have tended 

 to throw doubts on the propriety of including Celebes in the Australian realm, and 

 a Dutch naturalist, writing in 1909, from a study of the mammals, amphibians, 

 and fresh-water fishes — which afford some of the most trustworthy and valuable 

 evidence on this subject — has declared that Wallace's line " has no value as a 

 vol. in. — 14 



