THYLACINE AND DINGO 25 



earths and lacustrine deposits classed as pleistocene, 

 but also in the older pliocene beds at the top of the 

 true tertiary period. The marsupials represent a 

 lower grade of mammalian life, and, in the security 

 of Australia, of which they were in undisturbed 

 possession, they broke up into herbivorous, frugi- 

 vorous and carnivorous forms, in a fashion parallel 

 with the similar breaking up of the higher types of 

 mammals in other parts of the world. The thy la- 

 cine was the most powerful carnivore that came 

 out of the marsupial stock, and it acquired the 

 habits and much of the appearance of true dogs and 

 wolves. 



In Australia there is no longer a thylacine, and its 

 place in nature is occupied by a true dog, the dingo, 

 a medium-sized, prick-eared, brown animal very like 

 the pariah dog of India. It was the only large non- 

 marsupial mammal present in Australia before the 

 arrival of white man. Certainly it is a much more 

 recent arrival than the thylacine ; its remains have 

 been found in the pleistocene gravels, but most 

 authorities are agreed that it arrived in Australia by 

 human agency, in a semi- domesticated condition, 

 coming with the Asiatic human stock that first 

 reached Australia creeping from island to island 

 along the Malay Archipelago. However the dingo 

 may have come, there seems here to be a case of 

 one predacious animal replacing another and occupy- 

 ing its territory, for the thylacine has disappeared 

 from Australia and survives only in Tasmania, 

 which has not been reached by the dingo. But how 

 did the replacement actually take place ? The dingo 

 is certainly of a higher type than the thylacine ; it 



