282 THE CANADIAN NATURALIST. [Vol. viL 



Still another lesson may be learned here. It appears that our 

 present climate is separated from that of the glacial age by one 

 somewhat warmer, which was coincident with an elevated con- 

 dition of the land. Applied to Europe, as it might easily be, 

 this fact shows the futility of attempting to establish a later 

 glacial period between the Post-pliocone and the present, in the 

 manner attempted, as I must think on the slenderest possible 

 grounds, by Prof. Geikie in his late work " The Great Ice Age.'* 



The grandeur of those physical changes which have occurred 

 since the present marine animals came into being, is well illus- 

 trated by some other facts to which our attention has been 

 directed. Hecent excavations in the Montreal mountain have 

 enabled Mr. Kennedy to observe deposits of Post-pliocene marine 

 shells at a still hio-her level than that of the old beach above 

 Cote des Neiges, which was so long ago described by Sir Wm. 

 Logan and Sir Charles Lyell. The new positions are stated to 

 be 534: feet above the sea. Let us place this fact along with 

 that recorded by Prof. Bell in the Report of the Geological 

 Survey for 1870-71, of the occurrence of these same shells on 

 the high lands north of Lake Superior, at a height which, taking 

 the average of his measurements, is 547 feet above the sea level. 

 Let us further note the fact, that in the hills behind Murray 

 Bay and at Les Eboulements I have recorded the occurrence of 

 these remains at the height of at least 600 feet. We have then 

 before us the evidence of the submergence of a portion of the 

 North xlmerican continent at least 1000 miles in length and 

 400 miles in breadth to a depth of more than a hundred fathoms, 

 and its re-elevation, without any appreciable change in molluscan 

 life. 



Another important and impressive fact in this connection has 

 recently been brought out by Dr. Hunt in a paper on the Geology 

 of the South-eastern Appalachians. -'"^ He there shows that in 

 these mountains, which lie to the south of the region of the 

 great Post-pliocene submergence, the gneissose rocks have been 

 decomposed in place to enormous depths, without any of the 

 material beins; removed — a most strikina- contrast to the gener- 

 ally bare and scraped condition of similar rocks in the north. I 

 was struck very much with this fact several years ago, when^ 

 "under the guidance of my friend Dr. Tyson, T had an opportu- 



* Proceedings American Association, 1873. 



