236 THE ANTIQUITY OF MAN IN TASMANIA. 



however, of the greatest importance. He assumes 

 that:— 



(a) The isthmus between Tasmania and AustraHa 



existed during the younger volcanic period. 



(b) The dingo did not exist during this time in Vic- 



toria, otherwise it would have migrated with 

 the Tasmanians into the island. 



(c) The land-connection between AustraHa and Tas- 



mania was interrupted when Diprotodon and 

 the other gigantic marsupials existed on the 

 Australian continent. (See pag. 24.) 



A few years later C. Hedley (i) carefully discusses 

 the question, and what effect the so-called Bassian 

 Isthmus would have on the marine fauna. Though 

 Hedley's paper does not bear on the question of the 

 immigration of the Aborigines, it is of the greatest im- 

 portance with regard to this problem, because it pre- 

 sumes the existence of a land connection between Tas- 

 mania and Australia in recent times. Hedley points out 

 the difference in the marine fauna east and west of Wil- 

 son's Promontory, and his lists of the Adelaidian (west) 

 and the Peronian (east) fauna prove conclusively that 

 there exists a vast difiference. Such a faunistic difference 

 in an open sea can only be accounted for by the existence 

 of a former barrier of land which prevented the inter- 

 change of the faunas. I think there can be no difference 

 of opinion on this point. The sketch map accompanying 

 Mr. Hedley's paper is, however, erroneously constructed, 

 because he assumes that the isthmus connected only the 

 eastern part of Tasmania with Australia. This is cer- 

 tainly wrong, as a consultation of the Admiralty chart 

 would have shown him. The southern continuation of 

 Tasmania as constructed by Mr. Hedley is more than 

 problematical ; it is certainly not borne out by the sound- 

 ings marked on the chart. However, this does not de- 

 tract from the great importance of Hedley's conclusion 

 that a land connection must have existed between Tas- 

 mania and Australia within such a recent period, that 

 there was not time enough for a mixture of the two 



(i) The effect of the Bassian Isthmus upon the existing 

 marine fauna: a study in ancient geography. Proceed. Lin. Soc. 

 of New South Wales, 1903, PL iv., pag. 876-883. 



