240 THE AUSTRALIAN GLACIAL BEDS 



In the Australian region l glacial boulder clays are 

 found at the base of the beds containing the Glossopteris 

 flora in Victoria (Bacchus Marsh, Wild Duck Creek, 

 etc.), New South Wales, Queensland, South Australia, 

 West Australia and Tasmania. The most complete 

 succession is found in New South Wales, where there 

 is a great development of strata containing marine fossils 

 of Upper Carboniferous or Permian age. The lower 

 portion consists of an Upper and a Lower Marine for- 

 mation between which lies the Greta coal series with 

 Glossopteris, Gangamopteris, etc. Glacial erratics have 

 been found in both the Upper and Lower Marine beds, 2 

 and in places there are well-developed glacial horizons. 



Over the greater part of Australia there is an uncon- 

 formity at the base of these formations carrying glacial 

 erratics ; in certain areas, however, they pass downwards 

 without a break into strata containing marine Carbon- 

 iferous fossils. 



Prof. Seward 3 has pointed out that while the Palaeo- 

 zoic flora characterised by lepidodendroid plants existed 

 in the southern hemisphere before the Glossopteris flora, 

 the latter probably originated in the south, and flourished 

 there almost to the exclusion of the older plants during 

 the Permo-Carboniferous period, though the older flora 

 lived on in the northern hemisphere where the Glosso- 

 pteris flora only arrived in late Permian and Triassic 



1 Edgeworth-David, T. W., Q. J. G. S., lii., p. 289. 



2 For a detailed account of these beds see the same author in 

 Memoir, No. 4, Geological Survey of New South Wales, 1907. 



3 Presidential address, Section K, Southport Meeting of the British 

 Association, 1903. 



