Vol. 62.] GLACIAL PERIOD IN ABERDEENSHIRE, ETC. 39 



in which the shells are found, was probably due to its sheltered 

 position in the lee of the great rocky cliff of Gamrie Head. 



The amount' of submergence at Clava must have been decidedly 

 over 500 feet, which is greater than any of which we have evidence 

 along the coast farther east. If the submergence was due to a 

 depression of the land caused by the weight of ice laid upon it, 

 then the depression should have been greatest where the ice was 

 heaviest, namely, at the head of the Firth just where Clava is 

 situated, and where, as I have mentioned, the depth of ice may have 

 probably approximated to 5000 feet, or even more. 



Discussion. 



The President remarked that it would be strange indeed if a 

 cordial welcome had not been accorded to a paper by one who had 

 been a Fellow of the Society for nearly half a century, whose papers 

 on Glacial geology had been frequently published by this Society — 

 papers which, although theoretical questions were by no means 

 avoided in them, were specially characterized by the great number 

 and importance of carefully-recorded facts. 



Prof. P. F. Kendall observed that the Author, whose name was 

 one of the most revered in Glacial geology, had added a new division 

 to the Glacial Series of the district with which he dealt, in the shape 

 of the dark clay with the deep-water Arctic fauna. It was very 

 similar to a transported mass of Drift which he had seen and 

 described in the Isle of Man. Two problems still confronted the 

 geologist in that district ; one was the mode of deposition of the 

 Glacial deposits, the other raised the question of the land-levels in 

 that particular area during the Glacial Period. The distribution 

 of the erratics, the striations, and the contents of the deposits 

 seemed to group themselves in a remarkable manner. The direction 

 of the striations was entirely corroborative of the lithologieal 

 features : thus, the grey clay containing crystalline rocks derived 

 from the interior of the country was striated from the south-west, 

 while the other from the Old-Red-Sandstone area was striated from 

 nearly due south. In the Inverness district, on the other hand, 

 there appeared to be a low-level system of deposits associated with 

 striae from a south-westerly or north-westerly direction, while the 

 high grounds south of Clava bore striations running from due south. 

 These two results seemed, at first sight, to be contradictory, and it 

 would be most interesting to ascertain the mutual relations of the 

 two parallel sets of striae. The time had now arrived when it became 

 necessary for glacialists to group their facts with a freer hand, and 

 to deal with larger stretches of Drift- country. The available 

 evidence rather pointed to the influence of the Scandinavian ice- 

 sheet, than to the wane of the Highland Glacier and the waxing of 

 the Tay Glacier. As to the Clava shelly deposit, the speaker at 

 one time concurred with the late Dugald Bell in declining to regard 

 it as a marine deposit in situ. He subsequently abandoned that 

 view, but it might be necessary, with this new evidence, to return 

 to his former opinion. 



