2CO THE ANTIQUITY OF MAN IN TASMANIA. 



I therefore assume that the last glacial period in Tas- 

 mania coincided with one of the stages of the last glacial 

 period in Europe and America, and I presume that it 

 corresponds to the Wurmian, if we presume that when 

 the ice reached its last extension in Europe the causes 

 were such that they also affected other countries produc- 

 ing glaciation. When there was one of the smaller stages 

 in Europe, the causes producing glaciation were not 

 strong enough to produce it somewhere else. I admit 

 this is a theory pure and simple, but it is a workable 

 theory. According to my view the charges resulting 

 eventually in the formation of Bass Strait cannot have 

 commenced earlier than after the Wurmian stage (i). 



7. THE POST-GLACIAL RISE OF TASMANIA. 



As far back as 1888 Johnston, and later on in 1893 

 Montgomery, were of the opinion that the present level 

 of Tasmania is higher than it was during the glacial 

 period. The logical sequence of this view is that dur- 

 ing that time portions of Tasmania that are now dry 

 were under water ; in other words, the area of Tasmania 

 during the glacial period must have been smaller than it 

 is now. (See PI. II., Fig. i.) 



Subsequently Gregory emphatically shares this view. 

 A visit to Mount Lyell convinced him that during the 

 glacial period Tasmania must have been several hundred 

 feet lower than it is at present. 



Independently of these authors, I arrived at the same 

 conclusion when I ascended from the deep canon of the 

 Forth to the plateau of Barn Bluff. The difference in 

 height between the River Forth and the end of the 

 glacial valley on the plateau is 1,500 feet. The Forth 

 is one of the rivers that discharge into Bass Strait, 

 and it is obvious that its deeply cut 'canon can only have 

 been formed during a time of rise aggregating to 1,500 

 feet at least. 



(i) The maximum glaciation in Europe took place during 

 the Riss stage. If the glacial period in Tasmania corresponded 

 to this stage, the subsequent elevation and the volcanic out- 

 bursts would correspond to the Wurm stage. This is a proba- 

 bility which has to be considered, particularly in face of the 

 recent discovery of gigantic marsupials in Tasmania. 



