41 



ON THE SEQUENCE OF STRATA FORMING THE QUEBEC 



GROUP OF LOGAN AND BH.LINGS, WITH REMARKS 



ON THE FOSSH. REMAINS FOUND THEREIN. 



By Henrv M. Ami, M.A., F.G.S., &c., of the Geological Survey. 



(Presented to the Royal Society of Canada by Dr. G. M. Dawson, 



F.R.S. &c., May, iSqi.) 



(Abstract.) 



The paper dealt with the Geological focts and grounds upon 

 which the Quebec group rested and made it a necessary term in the 

 geological nomenclature of strata in North America^ but especially in 

 the Province of Quebec. 



The grounds, upon which the separation of the various terranes 

 constituting this natural group was based, as well as the faunal and 

 ihysical relations of its different members, were pointed out, showing 

 the validity of the existence of such a series of fossiliferous sedimentary 

 strata as that which Sir William Logan had recognized and Mr. Billings 

 so clearly demonstrated early in the ^'sixties." 



The removal ol the so-calied Hudson River black graptolitic series 

 of shales, etc., which are met with at Quebec City, at the west end 

 of the Island of Orleans, along the Marsouin River, and at many other 

 places in the Province of Quebec — at Norman's Kiln, in the State of 

 New York, and in Penobscot County, Maine, and other places in the 

 United States — from an uppermost position in the Ordovician System — 

 immediately above the Utica, or just below the base of the Silurian 

 System — was absolutely necessary in the light of facts whether 

 palaeontological or stratigraphical or in the light of other physical 

 reasons. 



The characteristics of this so-called " Hudson River " series of 

 rocks, when studied in the field as well as in closer detail, point clearly 

 to its intimate relation and association with the "Levis" of Sir William 

 Logan's Quebec group. The Levis and the Quebec formations or 

 terranes along with the Sil/ery, form a group of terranes geologically 

 and geographically closely related, which can be divided and sub-divided 



