AUSTRALIAN GLACIATIONS 209 
seems conclusive. There is an entire absence of marine deposits 
throughout the sections, while the existence of polished pavements 
in suitable situations beneath the bowlder clay cannot well be 
explained by any other hypothesis.t. In this particular the Victorian 
glaciation agrees with the South Australian of the same age, but there 
has occurred in the sequel a greater tectonic activity in Victoria than 
in South Australia, which has disturbed the surface contours and 
wiped out most of the contemporaneous glacial topography that 
is so striking a feature in South Australia. 
TASMANIA 
Rocks of Permo-Carboniferous age are very generally distributed 
throughout Tasmania. They give evidence of alternations of dry 
land with fresh water and shallow marine conditions. In places 
they contain productive coal measures. During the early stages 
of this geological period the present island of Tasmania formed 
part of the continental mass, and came under the glacial conditions 
which laid such a heavy hand on Australia at that time. 
The locality most favorable for the study of the glacial beds of 
Tasmania is on the north coast, in the neighborhood of Wynyard, 
where for a distance of five miles the bowlder beds are exposed 
along the beach. The beds dip at rather a low angle (5°—-10°), 
have a thickness of over 1,200 feet, and are overlain by fossiliferous 
beds of Eocene age. The beds, which have been worked out in 
great detail by Professor T. W. E. David (XXIII), consist, lithologi- 
cally, of characteristic tillites and conglomerates, all of which 
carry glaciated stones in greater or less numbers; and these are 
interbedded by thinner members consisting of sandstones and 
laminated shales. No glaciated floor has been discovered either 
here or elsewhere in Tasmania. The rotten Ordovician slates, on 
which the beds rest at Wynyard, are unsuited for the preservation 
of such a smoothed pavement, but the entire absence of marine 
remains throughout the very thick glacial series suggests the 
terrestrial origin of the deposits. 
tA polished surface beneath the bowlder clay in the Bacchus Marsh district is 
figured by Gregory, inhis Australasia, p.416 (Stanford’s ‘‘Compendiums of Geography,”’ 
New Issue, 1807). 
