379 



terior to tlie deposit of the IMontmorcncy Bridge limestone. At 

 Indian Lorettc the section is ahnost identical \Yith that of the Mont- 

 morency Falls. In the direction of Bean})ort I picked up in some 

 limestone quarries several brachiopoda which resemble Trenton 

 brachiopoda, but they were never determined in a regular way 

 They are now in the collection of the Jardin des Plantes at Paris, 

 with my other gatherings in North America during the years 1848, 



'49, and '50. 



Mr. Salter, wdio has examined the fossils picked up by Dr. 

 Bigsby at Montmorency, Beauport, and Indian Lorette, regards 

 them as indicating the Trenton limestone, and Mr. Logan gives a 

 list of fossils indicating for the limestone at the summit of the 

 cascade the Trenton age. In accordance with these two geolo- 

 gists, I regard those horizontal beds of limestone as representing 

 the Trenton limestone of New York, although I think the pres- 

 ence of the Alveolites repens, an Upper Silurian coral, in those 

 rocks, requires further inquiry before arriving at a final conclusion 

 on all the rocks found at Montmorency. 



The fifty feet of limestone pointed out by Mr. Logan at the foot 

 of the fall, and in immediate contact with the gneiss, I did not see, 

 and it is difficult for me to believe that fifty feet of limestone could 

 have escaped my notice when my attention was entirely fixed on 

 the stratigraphical phenomena of the section of Montmorency Falls. 

 But it is such a celebrated place for excursions and of such easy 

 access, that the verification of the question by a geologist can readily 

 be made. Even if these fifty feet of limestone are there, it is to be 

 proved that they contain Trenton fossils, which Mr. Logan does 

 not say. 



Messrs. Logan and Hunt, in previous works, (^^ Report of Prog- 

 ress of the Geological Survey of Canada, for the year 1847-48," 

 and, '•'' Esquisse Geologique du Canada^avec une Carte Geologique 

 du Canada,'^ Paris, 1855,) have described and colored all the 

 country east of Montreal, between Lake Champlain and Quebec, 

 as occupied exclusively by strata of the age of the Hudson River 

 group and Oneida sandstone^ or Richelieu slates and Sillery for- 

 mation, with some patches of Trenton limestone. It is certain that 

 the Taconic system occupies the main part of the country, and 

 that the geological map of Lower Canada is to be greatly modi- 

 fied to be put in harmony with the Primordial fauna formation. 



