Jlesozoic and Camozoic Geology and Paloiontology. 217 



4. The Post-plioceue deposits of Canada, in their fossil remains and 

 general character, indicate a gradual elevation from a state of depres- 

 sion, which on the evidence of fossils must have extended to at least 

 500 feet, and on that of far-traveled bowlder's to several times that 

 amount; while there is nothing but the bowlder clay to represent the 

 previous subsidence, and nothing whatever to represent the supposed 

 previous ice-clad state of the land, except the scratches on the rock 

 surfaces, which must have been caused by tlie same agency which de- 

 posited the bowlder clay. 



5. The peat deposits, with fir roots, found below the bowlder clay 

 in Cape Breton, the remains of plants and land snails in the marine 

 clays of the Ottawa, and the shells of the St. Lawrence clays and 

 sands, show that the sea at the period in question had nearly the tem- 

 perature of the present Arctic currents of our coasts, and that the 

 land was not covered with ice, but supported a vegetation similar to 

 that of Labrador and the north shore of the St. Lawrence at present. 

 This evidence refers not to the later period of the Mammoth and the 

 Mastodon, when the re-elevation was perhaps nearly complete, but to 

 the earlier period contemporaneous with, or immediately following the 

 supposed glacier period. In my former papers on the Post-pliocene of 

 the St. Lawrence, I have shown that the change of climate involved is 

 not greater than that which may have been due to the subsidence of 

 land, and to the change of the course of the Arctic current, actually 

 proved by the deposits themselves. 



It has long been known to geologists, that in northeastern America, 

 two main directions of striation of rock surfaces occur, from north- 

 east to southwest, and from northwest to southeast; and that locally 

 the directions var}^ from these to north and south, and east and west. 

 It would seem that the dominant direction in the valley of the St. 

 Lawrence, along the high lands to the north of it, and across western 

 New York, is northeast and southwest; and that there is another 

 series of scratches running nearly at right angles to the former, across 

 the neck of land between Georgian Bay and Lake Ontario, down the 

 valle}'' of the Ottawa, and across parts of the eastern townships, con- 

 necting with the prevalent south and southeast striation, which occurs 

 in the vallej'^s of the Connecticut and Lake Champlain, and elsewhere 

 in New England, as well as in Nova Scotia and New Brunswick. 

 What were the determining conditions of these two courses, and were 

 they contemporaneous or distinct in time? The first point to be set- 

 tled in answering these questions is the direction of the force which 



