COTEAU DES PEAIR1ES. 197 



AVoods Dr. Bigsby found the Pentamerus Kniglitii, a 

 fossil characteristic of the upper Silurian rocks ; but 

 granite is the chief constituent of the islands and 

 shores of the lake. The River Winipeg flows wholly 

 within the granite district, and has the lake-like dilatations 

 and other characteristics of the streams which traverse 

 the " intermediate primitive rocks." The wide extent of 

 land which its reuniting arms enclose is remarkable. 

 One of its affluents, named English River, issues from 

 Lake Sal, which lies near the water-shed, dividing the 

 Winipeg basin from that of James's Bay. The Berens 

 River which falls into Lake Winipeg, issuing from the 

 common brim of the same basins further north, in the vici- 

 nity of the sources of the Severn River, affords a canoe 

 route to Hudson's Bay. From my own observations in 

 1819, and Mr. Barnston's at a later period, it has been 

 ascertained that limestones of the silurian epoch occur on 

 the northern flank of the " intermediate primitive belt," as 

 well as in the basin of Lake Winipeg. The Red River, 

 which has been already repeatedly referred to, and which 

 to prevent confusion with its southern namesake it would 

 be well to call Osnaboyna, lies wholly to the westward of 

 the " intermediate belt," and has a direct course from 

 Lake Travers of 300 geographical miles. The sandy 

 ridge named Coteau des Prairies, or Hauteur des Terres, 

 separates its upper part from the Missouri valley ; but 

 the metamorphic rocks which present themselves around 

 the sources of the Mississippi and its tributary the St. 

 Peter, are also visible near Lake Travers. In the lower 

 part of Red River limestone crops out in one place only, 

 and is quarried by the settlers. Elsewhere the rocks are 

 concealed by the sandy deposit forming the soil of the 

 prairies, along whose eastern border the river flows. Major 



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