250 A LATE GLACIAL STAGE IN" THE LEA TALLEr. [Juue I9I2, 



DlSCTJSSION^. 



Mr. Clement Eeid welcomed the paper as one of the most 

 important contributions to Pleistocene geology that had been 

 made of recent years. It was particularly valuable, as the Arctic 

 deposit yielded so prolific a fauna and flora, which were being so 

 carefully studied. In these Arctic deposits in Britain, it was 

 noticeable that traces of man were extremely rare and local. 

 The speaker advised caution, before accepting as a criterion of 

 relative age the height of terraces. He pointed to Hoxne as an 

 example of what may have happened. If the silted-up valley at 

 Hoxne had been re-excavated, so as to leave only terraces of the 

 various fluviatile deposits clinging to the sides of the valley, we 

 should be told that the highest terrace was the oldest, while the 

 most recent occupied the bottom of the valley. It was only 

 the clear vertical superposition of the different deposits at Hoxne 

 that enabled observers to avoid this mistake. 



Mr. Eeginald Smith said that he was gratified to notice in 

 England a growing scientific interest in Paleeolithic man, and 

 congratulated the Author on making an important addition to the 

 existing evidence for considerable changes of climate since the 

 Boulder Clay. There should be a ruling as to what constituted 

 the Ice Age, as some investigators regarded anything after the 

 great glaciations as post-Glacial ; and others, in agreement with 

 Continental evidence, included several oscillations of the ice-sheet 

 that occurred during the late Palaeolithic or Cave Period. He 

 ventured to doubt whether the stratigraphy in I^orth-East London 

 gave the chronological sequence of the implements, for those shown 

 as the earliest, brown and rolled, with a cutting-edge all round and 

 twisted sides (at least on one), were of St. Acheul type ; while that 

 exhibited as a later specimen was lustrous and unrolled, but of 

 Chelles form. Mr. Worthington Smith had noticed brown imple- 

 ments in his ' contorted drift ' of this area, which were evidently 

 the sweepings of higher ground, and included some specimens 

 earlier than those covered by the deposit. A recent paper on the 

 Rhine loess had put the earlier and later parts of that formation 

 into their proper places in the Palaeolithic scheme, and investigators 

 in this country seemed to be on the road to a satisfactory equation 

 of British and Continental Palaeolithic deposits. 



Mr. W. Whitae:er, while admiring the ingenuity of Mr. Eoid's 

 explanation of how a small mass with the appearance of belonging 

 to a higher terrace might really be newer than another small mass 

 at a lower level, suggested that an explanation which might serve 

 in regard to a brickyard-section some 50 feet deep, could hardly do 

 so in the case of a valley four times as deep and several miles wide. 



Mr. G. W. Lamplugh congratulated the Author upon the extreme 

 interest of his subject and upon the thoroughness of his work. 

 The speaker had been constantly impressed in the northern and 

 western Midlands with the proofs of severe and prolonged erosion 

 since the period of maximum glaciation, which was evidently a 

 remote event in most parts of the interior of England. This erosion 

 was active, however, long before the great ice-reservoirs of the 



