OF ARTS AND SCIENCES. 185 



" Montreal, October 30, 18G0. 

 "To M. Jules Marcou. 



" My dear Sir, .... I have read your Geological History (in 

 * Geology of North America,' p. 99, Chapter IX., 4to, Zurich, 1858) 

 with great pleasure. That work contains many views which are pre- 

 cisely in accordance with those which I have long entertained, but 

 never saw in print before. Professor Dawson informs me that you 

 are about to investigate the Primordial Zone of North America, or the 

 Taconic system of Emmons. I am glad that you have taken up this 



subject T have been attached to the Geological Survey of 



Canada only four years, and the Taconic question, so far as it has 

 been investigated here, was settled long before I ever saw either Pro- 

 fessor Hall or Sir W. E. Logan. Hall, although not on the Survey, 

 was the palcEontological adviser, and he decided that the Quebec rocks 

 were Hudson River, because they contained Graptolites. Taking 

 these rocks as a starting point, Sir William, with immense labor, 

 traced out the geographical distribution and physical succession of all 

 the others in the disturbed region of Canada East. You will see that, 

 if there has been any mistake made, it originated in Hall's determina- 

 tion of the fossils of the Point Levis or Quebec Graptolites. Hall's 

 mistake, I think, is partly due to his ignorance of the geology of 

 Europe. He has always been of opinion that in Europe Barrande's 

 Primordial Zone overlies the Lower Silurian. You will see by refer- 

 ence to Foster and Whitney's ' Report on Lake Superior,' page 318, in 

 the comparative table which he gives on the European and American 

 formations, that he places the ' alum schists and argillaceous schists 

 of Northern Europe with Graptolites, Olenus, Ampyx, etc.,' above 

 the ' Orthoceratite limestone.' Now, it is well known that the 'alum 

 slates ' of Sweden constitute the Primordial Zone, or An^elin's 

 Regiones A, B, and also that they underlie the ' Orthoceratite lime- 

 stone.' 



" Emmons is the man who actually made the discovery of the Primor- 

 dial Zone on this continent, and who is entitled to the credit ; and when 

 we consider that he has stood alone against all the leading geologists 

 of America for more than twenty years, it would be hard if his ... . 

 opponent were to come in and share the honor with him. 



" I made the above statements upon the supposition that it will be 

 proved by physical geology that the ' Cham plain series,' from the 

 Potsdam upwards, do overlie the Taconic rocks. I have examined 

 the fossils only, and such as I have seen appear to me to represent in 

 part the fauna of Angelin's Regie B C, and in part the Primordial 



