MACROPODID^E 169 



that it was a huge species of jerboa. Soon afterwards (1791) Dr. 

 Shaw very properly formed a new genus for its reception, which 

 he named Macropus, in allusion to the peculiar length of its hind 

 foot. By the name thus formed, Macropus giganteus, this kind of 

 Kangaroo has ever since been known in zoological literature. It is 

 the common Gray Kangaroo, called " boomer," " forrester," or " old 

 man " by the colonists, and frequents the open grassy plains of the 

 greater part of eastern Australia and Tasmania ; a figure being 

 given in the woodcut on p. 160. The muffle is partly covered 

 with hair, and the fourth premolar very short. Several varieties 

 are known. 



A sub-group, distinguished from the above by the naked 

 muffle, includes some very large and handsome species, which prin- 

 cipally dwell in rocky mountain ranges, as M. rufus, the great Red 

 Kangaroo, M. antilopinus, and M. robustus. The fourth premolar is 

 of large or medium size in these forms. Remains of M. giganteus 

 occur fossil in the Pleistocene of Australia, where we also find the 

 allied extinct M. titan, which attains somewhat larger dimensions, 

 M. robustus also dates from the same geological epoch, where it was 

 accompanied by two allied types known as M. altus and M. cooperi. 



The second group includes the larger Wallabies, which are 

 smaller than the true Kangaroos, with a brighter and more 

 variegated coloration. The palate is generally more incomplete 

 than in the typical group ; and in the molars the anterior talon is 

 connected with the first transverse ridge by an external instead of 

 a median longitudinal bridge. The members of this group are 

 frequenters of forests and dense impenetrable brushes and scrubs, 

 and hence are often called Brush Kangaroos, though a native name, 

 " Wallaby," is now generally applied to them. There are several 

 species, of which M. rujicollis, M. ualabatus, M. parryi, and M. agilis 

 are the best known. 



M. ualabatus and M. parryi are found fossil in the Pleistocene 

 deposits of Australia. In those beds we also meet with remains of 

 several very large extinct species, which appear to be allied to those 

 Wallabies in which the fourth premolar is large and elongated, all 

 of them agreeing with the Wallabies in the absence of the median 

 bridge between the first ridge and talon of the molars. These fossil 

 forms comprise M. brehus, in which the skull was probably about 

 one foot in length, and M. rcechus, and M. anak, which were of some- 

 what inferior dimensions. In the last-named species the length of 

 the fourth upper premolar is equal to that of the first and half of 

 the second molar. 1 



The third and last group of the genus includes the small 



1 For the characters of these species and the undermentioned distinct genera, 

 see Owen's Extinct Mammals of Australia (1877), and Lydekker's Catalogue of 

 Fossil Mammalia in the British Museum, pt. v. (1887). 



