222 PROCEEDINGS OF THE CANADIAN INSTITUTE. 



must of course have taken place after the deposition of the strata 

 folded. Mr. Drummond's views offer no explanation of the south- 

 westerly debouchment of the Nepigon, Black and Thnnder Bays, which 

 is south and a little west, not eastward as by his theory it ought 

 to be; they do not elucidate the problem how the lakes became 

 contracted, how their overflow was turned from the old direct line to 

 the Gulf of Mexico, to that by way of Chicago ; then in succession to 

 that by Niagara or the Trent down the Mohawk and Hudson valleys ; 

 these closing, to the Kichelieu and Champlain valleys, and finally to 

 the Gulf of St. Lawrence. If my supposition is correct, Lakes Erie 

 and St. Clair cannot be recent lakes, in the sense Mr. Druramond 

 states, but are the shrunken remains of one that covered all Western 

 Ontario and the lower peninsula of Michigan, in times quite recent, 

 I admit, compared with the antiquity of some lake basins ; and I 

 regard it as almost trifling to talk of the Straits of Mackinaw as 

 existing in those old days, for the level alluvial soil stretching broadly 

 from west of the Sault Ste. Marie to Lake Michigan precludes the 

 idea that there were any such straits until a very recent epoch. I 

 think, moreover, that Mr. Drummond must form a grander concep- 

 tion of the forces at work in framing continents before he can com- 

 prehend the wide distribution of precisely similar forms of life, or the 

 great superficial extent of many strata, e.g., the Potsdam sandstone, 

 which he may trace from Gaspe to Missouri. 



Another imposing feature of the old Laurentian shore may have 

 been a great volcanic range. By analogy, it must have been near 

 the water ; allowing for the wearing of the cliffs, we may suppose it 

 southward of the present Lake Superior coast, but thei-e are no data 

 yet for locating it with precision. The only guess I have come 

 across as to the locality of any volcanoes about Lake Superior, is one 

 attributed to Dr. Selwyn, that there was a great burning mountain 

 where Lake Nepigon now is, which, in blowing itself away, made the 

 basin of Lake Nepigon. I see nothing to confirm that theory. Lake 

 Nepigon is not in a deep basin or immense crater ; it seems to be 

 simply a bit of Lake Agassiz (the former extended Lake Superior 

 when it stood at a high level) left when the level of Lake Superior 

 fell — as the Georgian Bay might be left an independent lake if Lake 

 Huron were to be lowered. The locality where I have been aVjle to 

 give most study to the eruptive traps, lies between the Current and 



