﻿496 Canadian Record of Science. 



conglomerates from those found in the associated slates 

 and limestones, shew that these are of the horizon of the 

 Calciferous formation of the Ottawa district, and that the 

 upper part of the Sillery would therefore be the equivalent 

 of the Potsdam sandstone, which in that area has been 

 conclusively proved to be the lower part of the Calciferous 

 formation. The Levis graduates upward into the Chazy, 

 as certain beds near the top of the series contain fossils 

 which bear a close resemblance to those obtained from 

 the true Chazy beds elsewhere. 



The peculiar development of strata which compose 

 the hill on which the city of Quebec is built, has also been 

 a fruitful source of controversy. They were for many 

 years supposed to be a portion of the Levis division, 

 though differing in many respects from the typical strata 

 of that formation as developed on the south side of 

 the river, both in physical characters and in the nature of 

 the contained fossils. They were subsequently regarded 

 by some observers as the equivalents of the Utica and 

 Hudson Kiver formations. A careful study of the fauna 

 of the city rocks has, however, very conclusively disproved 

 both of these views, in so far at least as the greater 

 portion of the strata are concerned. The fossils, of which 

 large collections have been made, show that these are 

 more closely related to the base of the Trenton formation, 

 and that they represent a peculiar development about the 

 horizon on the Black Kiver or near the top of the Chazy. 

 They are separated from the Utica and Lorraine on the 

 north by a fault which skirts the north flank of the 

 city along the valley of the St. Charles Kiver, and from 

 the Sillery formation by another fault which passes to the 

 south of the city, in front of the Citadel, and which comes 

 to the north shore of the St. Lawrence about two 

 miles above the city. 



The strata in the city itself are, however, thrown into a 

 series of folds ; and from the presence of certain fossils at 



