﻿Vol. 64.] AGE IN SOUTH AT7STKALIA. 261 



Pleistocene, Cambrian, or any other age, had a highly-characteristic 

 appearance, due presumably to the haphazard assemblage of diverse 

 materials. At a distance all looked alike, and it was only on close 

 examination that the hardening due to infiltration of silica, and 

 other differences, became apparent. 



Some glacial deposits of early age in the Yaranger Fiord, described 

 before the Society in 1897 (Quart. Journ. Geol. Soc. vol. liii, p. 1 37), 

 rested on a glaciated platform of the quartzite with which the 'till' 

 was interbedded. The question had then been raised by the Presi- 

 dent how the sand could have been sufficiently indurated to retain 

 striations so soon after its deposition. Various explanations had 

 been suggested, but none were wholly satisfactory. He enquired 

 whether a similar platform had been observed under the Australian 

 * till.' It would be interesting also to know whether there was proof 

 that the ice had descended to or below the sea-level of the period. 



Dr. J. M. Maclaren said that the notes which he had communi- 

 cated might be considered a contribution toward the discussion of 

 Mr. Howchin's paper. They were apparently intended to prove no 

 more than that certain rocks, claimed by Mr. Howchin as ' erratics ' 

 in glacial beds, were merely fragments faulted in from the adjacent 

 quartzites. While the Authors of the second paper had made out a 

 fair case for their point, they had thrown no light on the origin of 

 the beds as a whole. All the Archaean and Cambrian conglomerates 

 that he had seen were of the boulder-bed type, and he offered, as a 

 general suggestion, a torrential origin for many of these, comparing 

 them in point of view of matrix, of dispersion, character, and size 

 of boulder, and of extent of deposit, with the great boulder-beds 

 now being formed at the head of the Assam Valley, at the debouch- 

 ments of the Lohit Brahmaputra, Dihon, and other Eastern 

 Himalayan rivers. Although these were fluviatile deposits, it 

 was quite conceivable that striated pebbles might occur in them — 

 pebbles that, in a single monsoon season and without loss of striaB, 

 were transported from terminal moraines to the broad valley-plains 

 at the mouths of the gorges. With regard to the South Australian 

 conglomerates under discussion, his knowledge of them was much 

 too limited to permit the expression of any opinion as to their 

 origin. 



Mr. E.. D. Oldham commented on the completeness of the 

 evidence which the Author of the first paper had brought forward, 

 and the masterly way in which it had been marshalled to show that 

 the beds described by him presented a combination of characters 

 which, so far as we knew, was only to be found, as a whole, in beds 

 of glacial origin. He did not think that this conclusion was seriously 

 invalidated by the suggestion made by the Authors of the second paper 

 regarding the possibility of a different origin of a part of the beds 

 dealt with by Mr. Howchin. He had, himself, been struck with 

 the resemblance shown by the specimens and photographs to some 

 ancient deposits of presumably-glacial origin with which he was 

 acquainted, and more especially with the Blaini ' conglomerate ' of 

 the Outer Himalayas, which had undergone a very similar amount 



