﻿1861. J 



HECTOR ROCKY MOUNTAINS, ETC. 



415 



Anomia Flemingii. 

 Inoceramus Cedarensis. 

 Leda Hindi. 



Natica obliquata. 

 Avellana concinna. 

 Ammonites (sp. indet.). 



Of those from my collection has been determined the Leda Hindi ; 

 and, in addition, Ostrea lugubris, scales of Ctenoid Fishes, Annelide- 

 tubes and Plant-remains were also found. Traces of these beds were 

 observed to the south of the Qu'appelle River, and also on the North 

 Saskatchewan on the left bank, a considerable distance above the 

 Eagle Hills. Mr. Hind also observed them to form part of the high 

 escarpment of the Duck and Hiding Mountains which overhang the 

 lakes, reaching an altitude of 1000 feet ; and it was at 500 feet from 

 the summit that he detected these strata. 



The group has not been distinguished from the next on the 

 map which accompanies this paper ; but, from the more resisting 

 texture of these shales, it is probable that they occupy a larger area 

 of the lower plains that have been subjected to such great denudation 

 than any other group of strata. 



Group D. — At Fort Ellice the banks of the Assineboine are 240 

 feet high, and in general their structure is obscured by vegetation, 

 but at one point a recent slide displayed a partial section of the bank. 

 The upper part consisted of the comminuted fragments of the last- 

 described shale, along with beds of pure sand, and also the more com- 

 mon yellow drift. Close to thewater's edge, masses of strata of tenacious 

 calcareous clay were exposed, of a dark-purple colour, but presenting 

 a weathered surface decomposing into a ferruginous earth. Along 

 with these strata were two beds of soft clay-ironstone about 4 feet 

 apart ; the lower one half a foot thick and rather compact, the upper 

 one concretionary, forming thick nodulated masses, the surfaces of 

 which show the cone-in-cone structure. At this place only a few 

 fragments of the nacreous shell of Bacidites were found, but suffi- 

 cient, along with the mineral resemblance, to identify these beds with 

 group D in the vertical section. At the elbow of the South Saskat- 

 chewan, where that river cuts through the great prairie-coteau, the 

 boulder-drift is seen to rest on strata of purple clay (fig. 1, p. 395), 

 with nodular masses of ironstone, having veins and cavities filled 

 with calc-spar. These Septaria are in great numbers, and, when 

 broken, are found to include fragments of the following fossils : — 



Baculites compressus. Cardium. 



Inoceramus (/. Crejpsii of Roemer Exogyra. 



and Conrad). Astarte Texana. 



Pholadomya occidentalis {Morton). Cytherea. 



The outcrop of these Septaria- clays has a clear relation to the 

 great prairie-ridge which is cut through by the South Saskatchewan 

 at this point, and continued to the north-west by the Eagle and other 

 hills to near Fort Pitt, where it hems in the North Saskatchewan in 

 like manner, the banks having an altitude of 500 feet, and also dis- 

 playing sections of the strata with the same fossils. At the base of 

 the Eagle HilLs, and wherever they prevail, they form lofty and 

 ruinous banks, the strata breaking away in great slices, which slide 

 forward successively. I have counted as many as thirteen such slides 



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