No. 2.] DAWSON — POST-PLIOCENE. 167 



across the country in a North-east and South-west direction. Like 

 our Canadian eskers or " Boar's backs," they are now admitted 

 to be of marine origin, and are attributed to current action and to 

 the waves, though floating ice has no doubt, as in Canada, contri- 

 buted in some cases to their formation. 



Mr. Milne Home gives a graphic description of the Post-plio- 

 cene deposits in the neighbourhood of the Frith of Forth, and 

 many of his numerous sections might have just as well been taken 

 from Canadian deposits. He thus sums up the causes of the phe- ' 

 nomena, assuming that at the beginning of the period the land 

 was submerged. 



" The ocean over and around Scotland was full of icebero-s and 

 shore ice, which spread fragments of rocks over the sea bottom 

 and often stranded, ploughing through beds of mud, sand, gravel, 

 and blocks of stone, and mingling them together in such a way 

 as to form the ' Boulder-clay.' The land thereafter gradually 

 emerged, during which time the long ridges or embankments of 

 gravel called 'kames' were formed." 



Mr. Mackintosh's observations go mainly to show that in Eng- 

 land, as in Canada, even the lower drift and rock striation are due 

 to a great extent to floating ice and not to glaciers, and he extends 

 this conclusion even into the lake district of England. 



It is also worthy of remark that the long-received doctrine that 

 glaciers are powerful eroding agents, which the author showed in 

 a paper in this journal, in 1866, to be without foundation, is only 

 now beginning to be discredited in England. I shall refer to this 

 in the sequel, and in the meantime may direct attention to an in- 

 teresting paper on the subject by Mr. Bonney, F.Gr.S., in the 

 Journal of the Geological Society for August, 1871. 



It would further appear that, after the glacial period, in the 

 Post-glacial, the British land rose to a level higher than that which 

 it at present exhibits, then sunk again, and re-emerged in the 

 modern period. Evidences of this later submergence have not 

 been recognized in Canada, but in the inland area they have been 

 detected by Hilgard and by Andrews. 



Since the publication of the first part of this memoir. Prof. 

 Hilgard has discussed the subject of the southern drifts of the 

 Mississippi valley at the meeting of the American Association at 

 IndianajDolis ; and I am indebted to that gentleman and to Prof. 

 Andrews, of Chicago, for much information on these deposits and 

 their relation to those of more northern regions. 



