6l8 MANUAL OF ZOOLOGY. 



gical epochs as they are now. In the Post-pliocene period we 

 know that Austraha was occupied by Kangaroos, Kangaroo- 

 rats, Wombats, Phalangers, and Carnivorous Marsupials, in 

 every way representing the living Marsupials in zoological 

 value, but specifically distinct, and generally of gigantic size. 



In the same way. South America at the present day is espe- 

 cially characterised by a Mammalian fauna, containing many 

 peculiar forms, the Edentata being especially conspicuous, and 

 having a larger representation than in any other region. Simi- 

 lar but distinct forms, however, are found to have existed in 

 South America anterior to the creation of any existing species. 

 Thus, the modern Sloths of South America are represented by 

 the colossal Mylodon, Megalonyx, Scelidotherium, and Megathe- 

 rium. The little armour-plated Armadillos are represented by 

 the equally colossal Glyptodon. The Llamas — representing in 

 South America the Camels of the Old World — are represented 

 by the curious extinct genus Macraucheiiia. The Platyrhine 

 Monkeys have their extinct representatives. Fossil Tapirs 

 take the place of the two existing species ; and the Peccaries 

 are represented by at least five extinct species of Dicotyles. 



Similarly, India is at present the only country in which four- 

 horned Antelopes occur j and it is in the Sivalik Hills that 

 there have been found the two gigantic four-horned Antelopes 

 which constitute the genera Sivatherium and Bramatherium. 



In Europe, again, the Mammalian fauna of the later Tertiary 

 periods is much more closely alhed to that now characterising 

 the Old World, than to that of the New. We have the Lion, 

 Bear, Wolf, Fox, and other well-known Carnivora. Elephants, 

 Rhinoceroses, and Hippopotami, then as now, are characteristic 

 Old World forms. The Ruminants are equally characteristic 

 of the eastern hemisphere, though not exclusively confined to 

 it, and they have numerous and varied representatives in later 

 Tertiary deposits. The Giraffe is represented by the Hellado- 

 therium, and the Bactrian Camel by the Merycotherium of the 

 Siberian Drift. The fossil Quadrumana, . too, of Europe, all 

 belong to the Catarhine section of the order. 



It is unnecessary to pursue the subject further, but no law 

 is m.ore firmly established than this ; " That with extinct as 

 with existing Mammalia, particular forms were assigned to 

 particular provinces ; and that the same forms were restricted 

 to the same provinces at a tormer geological period as they 

 are at the present day" (Owen). It is to be borne in mind, 

 however, that the law, as just stated, holds good for the later 

 Tertiary period only, and does not apply, in any manner that 

 admits of being traced, to the earlier geological epochs. 



