ANTARCTICA: A VANISHED AUSTRAL LAND. 305 



dered into i^ortb America). The present marsupials, however, of South 

 America (the opossums) exhibit wide differences from those now living 

 in Australia; it is therefore not improbable that their ancestry must 

 be traced from forms once living, but now found fossil only, in North 

 America. The singular implacental animals now living in Australia 

 are but the remnants of a much more extensive order; for there van- 

 ished at a comparatively recent geological i^eriod other marsupials still 

 more remarkable, especially for their gigantic size. Of these the Dip- 

 rotodon attained to the proportions of a rhinoceros or a hippopotamus, 

 and the Noiotherium to that of a tapir; while the ThyJacoJeo was a 

 gigantic carnivore that j)robably i^reyed on the titanic kangaroo of its 

 own time, an animal twice as tall as the largest " old man " kangaroo 

 {Macrojms {jiganten.s) of to-day, which has been known to measure 

 nearly 6 feet from the point of the nose to the root of the tail. The 

 interest of these remains has largely increased through the discoveries 

 of South American paleontologists who have quite recently disinterred 

 most unexpected treasures from the early Tertiary formations of Pata- 

 gonia, the first fruits, there can be little doubt, of a large harvest of 

 remains, which will certainly shed, as those already obtained have 

 done, a flood of light on the pedigree of many of the vertebrata. Among 

 these treasures not the least important are the remains of marsupials 

 closely related to the DiprotodoUj the Thylacoleo, and the "Tasmanian 

 devil," which, in the Pliocene age, flourished in Australia in such 

 abundance. 



Turning for a moment to still another group of the vertebrata, we 

 find that, in such widely separated spots as New Zealand, Patagonia, 

 and the Falkland Islands, there occur identical species of different 

 families of fresh-water fishes. The southern salmon {HaplocMtonidw) 

 and the southern pikes {Galaxiidw), which are unknown north of the 

 equator, and which could not traverse the wide expanse of sea dividing 

 them, are common to all of these localities. Our highest authority on 

 ichthyology. Dr. A. Griinther,P. R. S., of the British Museum, has shown 

 that between the freshwater fishes of Africa and Australia there is, 

 though not an extensive, yet an unmistakable affinity; while, with 

 many points of close resemblance between them, the African and the 

 South American genera are distinct, which indicates " that the separa- 

 tion of these continents must have been of old date." 



Mr. Wallace has, in his great work on The Distribution of Animals, 

 pointed out how insects, as a whole, show a decided interrelation 

 between Australia and South America. Indeed, he believes that the 

 Buprestidw, a family of brilliantly metallic beetles, had their original 

 development in temperate Australia, and spread thence, while of the 

 longicorn beetle (so named from the long antennee they possess) several 

 genera are common to South America, Australia, and New Zealand, 

 indicating that there must have been some means of communication 

 between these countries other than at present. Both the families of 

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