CHAP. XVII.] MAMMALIA. 251 



The well-known Kangaroos are the most largely developed 

 family of Marsupials, and they appear to be the form best adapted 

 for the present conditions of life in Australia, over every part of 

 which they range. One genus of true terrestrial kangaroos {Dor- 

 copsis), inhabits the Papuan Islands, as do also the curious tree 

 kangaroos (Dendrolagus) which, without much apparent modifica- 

 tion of form, are able to climb trees and feed upon the foliage. 

 The genera, as established by Mr. Waterhouse, are as follows : 

 Macropus (4 sp.). West, South, and East Australia, and Tasmania 

 (Plate XII., vol. i. p. 441) ; Osphranter (5 sp.), all Australia ; 

 Halmatunts (18 sp.), all Australia and Tasmania ; Petrogale (7 

 sp.), all Australia ; Dendrolagus (2 sp.), New Guinea (Plate X., 

 vol. i. p. 414) ; Dorcopsis (2 sp.) Aru and Mysol Islands, and 

 New Guinea ; OnycJiogalea (3 sp.). Central Australia ; Lagor- 

 chestes (5 sp.). North, West, and South Australia ; Bettongia (6 

 sp.), West, South, and East, Australia, and Tasmania ; Hypsi- 

 prymnus (4 sp.). West and East Australia, and Tasmania. 



Extinct Macropodidce. — Many species of the genera 3facropus 

 and Hypsiprymnus have been found in the cave-deposits and 

 other Post-Tertiary strata of Australia. Among the extinct genera 

 are Protemnodon and Sthenurus, which are more allied to the 

 tree-kangaroos of New Guinea than to living AustraHan species ; 

 the gigantic Diprotodon, a kangaroo nearly as large as an elephant ; 

 and Nototherium, of smaller size. 



Family 81.— PHALANGISTID^. (8 Genera, 27 Species.) 



The Phalangistidse, or phalangers, are one of the most varied 

 and interesting groups of Marsupials, being modified in a variety 

 of ways for an arboreal life. We have the clumsy-looking 

 tail-less koala, or native sloth ; the prehensile-tailed opossum-like 

 phalangers ; the beautiful flying oppossums, so closely resembling 



