﻿1861.] 



HIX'TOB, ROCKY MOUNTAINS, ETC. 



439 



and trie river- channel crosses the strata of gneiss and bedded green- 

 stones at right angles, following the direction of the dip. 



Eainy Lake has its length agreeing with the strike of the strata, 

 which is here more nearly east and west than before. 



Between Eainy Lake and the Lake of the Woods the superficial 

 deposits again cover all rocks from view, and when the north end of 

 the latter lake is reached and they are again exposed, their general 

 strike is now changed to almost north and south, agreeing with the 

 greater axis of the lake, just as Eainy Lake agrees with the strike 

 of the eastern district. The descent from the Lake of the "Woods to 

 Lake Winnipeg is by successive groups of falls, between which the 

 river forms lake-like expansions, which lie generally at right angles 

 to its main course. 



The first part of the Eiver Winnipeg flows across vertical strata, 

 and then enters a granitic district very similar to that passed through 

 between the Lake of the Thousand Isles and Sturgeon Lake. 



The strike of the rocks in this region is generally a little to the 

 east of north, and the nature of the strata is very similar to that of 

 the country east of Eainy Lake, but less disturbed by dykes. 



No trace was observed of the existence of the schistose rocks on 

 the west flank of the axis, the gneissose rocks continuing for the 

 whole way to Lake Winnipeg. 



Silurian Bocks. — Mr. Hind, who had favourable opportunities, 

 from having coasted along Lake Winnipeg and the other lakes that 

 lie in this formation, gives an interesting account of its development 

 in his recent work (' Canadian, Assineboine, and Saskatchewan 

 Expl. Exped.' ch. xxxviii.): his fossils having been submitted to 

 Mr. Billings of the Canadian Geological Survey, the following groups 

 were identified as occurring in the Winnipeg basin ; all of them are 

 Lower Silurian:— 



1. Chazy Formation. 3. Trenton Limestone. 



2. Bird's-eye Limestone. 4. Hudson Eiver Group. 



Of these I only saw the last at the same place that Dr. Owen 

 examined and recognized the proper age of the beds in 1848 — namely, 

 at the Lower Fort Garry on Eed Eiver. Here there is a bench of 

 magnesian limestone exposed in the bed of the river when the 

 water is low, and which is then quarried for building-purposes. As 

 the river was high when I was there, this section was not visible, 

 but from fragments lying on the bank the following fossils were 

 obtained : — 



Cyathophyllum. Ormoceras Lyonii (S fakes). 



Colunmaria alveolata (Hall). Strophomena plano-convexa. 



Favestella (Favosites basaltica of D. Orthis ; var. of 0. Lynx. 



Owen). Spirifera elegantula. 



Receptaculites occidentals (Salter). Maclurea. 



Rhynchonella incubescens (Hall). 



These fossils have been named for me by Mr. Salter, who has 

 kindly examined the few palaeozoic fossils that were procured. The 

 limestone is subcrystalline,of alight-buff colour with purple blotches, 



