20 G Proceedings of the Royal Society of Victoria. 



quite conceive tliafc others who were extreme glacialists 

 would concede that the authors had fully proved tlieir 

 point. 



Mr. Griffiths said that for purposes of discussion the 

 paper might be divided into two parts — the part which was 

 purely descriptive, and the part which offered explanations 

 of the appearances described. The latter part might be 

 divided into three principal propositions which were put 

 forward although not formally stated. The first was that 

 there were evidences locally of two glacial e})Ochs — one earl}^ 

 in the Permian, the other early in the Tertiary. The 

 second was that the boulder clay of each of these was due 

 to land ice, and not to marine transport by icebergs. The 

 third was that the submergence of the continent sufficient 

 to ffoat an iceberg at Bacchus Marsh, would reduce the 

 land surface to such a small area that it would be too 

 limited in area to breed icebergs, and too warm to 

 accumulate ice on account of its insularity. With respect 

 to the descriptive part of the paper, he had found 

 many discrepancies between the descriptions given b}' 

 the authors of the paper and the statements made by the 

 officers of the Geological Survej^ The Government officers 

 had given a section showing a thick bed of what had since 

 been termed Trias.-ic conglomerate, which the authors of the 

 paper had attributed to a different period, but did not give 

 a tripartite division, which Messrs. Officer and Balfour 

 stated to exist in the section desciibed on the Werribee 

 River. The Government officers, who were men of ex- 

 perience, had failed to recognise any glaciated rocks in 

 this sect-ion, although they had stated that a glacial con- 

 glomerate existed in the distiict. Of course, it sometimes 

 happened that through want of sufficient data, errors had 

 crept into the Geological maps, and he simply pointed 

 this out as showing that it wa.s advisable to carefully 

 weigh the evidence adduced before accepting it. Although 

 the Government geologists had not seen their way to 

 describe the bottom member of this section as a glacial 

 deposit, they had pointed out that the Mesozoic sand- 

 stone was composed of two members, the upper being a 

 sandstone and the lower being a conglomerate, and stated 

 that this conglomerate was due to marine action. They 

 recognised a difference, but attributed it to a different 

 cause. With regard to the ffrst proposition, that there 



