AUSTKALIAK MAMMALIA. 99 



kangaroos and kangaroo-rats, are numerically the most important 

 and the most broadly distributed of the several types, and com- 

 prise a diversity of forms, which are variously adapted to living 

 in the scrub, in the desert, along rocky and precipitous mountain 

 summits (Petrogale), or on trees. The arboreal genus Dendrolagus is 

 thus far known only from New Guinea and Queensland. The great 

 kangaroo (Macropus giganteus), inhabiting the southern half of 

 the continent of Australia and Tasmania, attains in the male a 

 length, from the tip of the nose to the root of the tail, of upwards 

 of five feet. The kangaroo-rats, rat-kangaroos, or potoroos (Hypsi- 

 prymnus), are diminutive forms, of about the size of a hare, with 

 rounded instead of elongated ears, and a general rat-like appearance. 

 The second family is that of the Dasyuridse, or native cats, a group 

 of carnivorous and insectivorous marsupials, which range in size 

 from the dimensions of a mouse to those of a wolf. The most dis- 

 tinctive forms belong to the genus Antechinus, a group of insect- 

 ivorous animals, which, in outward appearance, are but barely dis- 

 tinguishable from the ordinary mice. The most formidable member 

 of the family is the Tasmanian "tiger," or "hyena" (Thylacinus 

 cynocephalus), a striped carnivorous marsupial, having the general 

 aspect of a wolf or dog, which it also fully equals in size, measuring 

 as much as five feet in length. The third family is that of the 

 Myrmecobiida}, which includes but a single species, the native ant- 

 eater, or striped myrmecobius (M. fasciatus), a small squirrel-like 

 animal, of about the size of the common squirrel, inhabiting South- 

 ern and "Western Australia. The Paramelidae comprise the bandi- 

 coots (Perameles), small kangaroo-like animals of about the size of 

 the rabbit, and the singular pig-footed marsupial known as the 

 Choeropus, a graceful animal somewhat recalling in appearance 

 the mouse-deer of the Oriental region. The fifth family, the Pha- 

 langistidse, exhibits in its individual components a greater diversity 

 of form, and greater specialisation of structure, than is to be found 

 in any other mammalian family. As described by Wallace, we find 

 represented in this family the tailless koala, or native sloth (Phas- 

 colarctos); the prehensile -tailed opossum-like phalangers (Phalan- 

 gista); the beautiful flying-opossums (Petaurista, Belideus, Acro- 

 bata), so closely resembling in form the flying-squirrels of North 

 America and India, but often no larger than a mouse ; the dormouse- 

 like Dromicia, one species of which does not equal in size the ordi- 



