20 PARALLELISM OF THE QUEBEC GROUP. 



great importance, on account of its stores of mineral wealth ; and 

 everything therefore relating to its geological structure, is of 

 iuterest, not only in a scientific, but also in an economical point 

 of view. 



In 1860, Sir W. E. Logan, after having re-examined the whole 

 subject, came to the conclusion that the position, to which these 

 rocks had been previously referred, was too high up in the series, 

 and that they lie near the base, rather than in the upper half of 

 the Lower Silurian. This opinion was published in the Canadian 

 Naturalist and Geologist of December, in the same year.* Since 

 that time a vast deal of new evidence has been collected, all tend- 

 ing to prove that this view is the correct one. Endeavours are 

 being made, however, by means of pamphlets, published by Mr. 

 Marcou, of Boston, and circulated in Canada, the United States, 

 and Europe, to show that the Quebec group does not belong to 

 the Lower Silurian at all, and that it lies below the Potsdam 

 sandstone, in the primordial zone. But unfortunately for this 

 theory, the papers containing the physical and palaeontological 

 evidence, published by the Canadian Survey, are in the hands of 

 all the great European geologists, and have furnished them with 

 the means of forming their own opinions upon the subject. The 

 views of these men, are to us of the highest value, coming as 

 they do from those who by their world-wide experience and oft 

 tested ability, are acknowledged on all hands, to be the highest 

 authorities on all that relates to the lower palaeozoic formations. 



Sir R. I. Murchison, in his address to the Geological Section 

 of the British Association, in 1861, publicly announced his en- 

 tire concurrence with us in the important change that had been 

 made. 



M. J. Barrande has, in several papers published in the Bulletin 

 of the Geological Society of France, and in Bronn's Neues- 



* Thefos3ils upon which the age of the Quebec group was determined 

 were collected in May and June, 1860. On the l'2th of July I wrote to 

 Barrande, informing him of the discovery, and that they (the fossils) 

 proved that the Point Levis rocks belonged to a horizon near the base 

 of the second fauna. In August, I published the descriptions of the 

 trilobites in the Canadian Naturalist and Geologist, and on that occa- 

 sion the use of the designation "Hudson River Group," as the name of 

 the formation was first discontinued. Barrande communicated (in a 

 letter dated Paris, 14th August, I860,) the substance of my letter to Mr. 

 Marcou, and it was by him published in the proceedings of the BostOB 

 Natural History Society in November following. 



