104 



NORTH AMERICAN FAUNA. 



I mi. 27. 



and the right rather low. Xo feature of particular interest occurs 

 until Blackwater River, 28 miles below the Rock, is reached. This 

 stream at its mouth spreads out over a broad gravelly flat. Below 

 here the river makes a sharp bend and for several miles pursues a 

 westerly course, being bordered on the north by banks of gravel and 

 clay upward of 400 feet high. A few miles below where the river 

 turns northward again, or 10 miles below the Blackwater, Red Rock 

 River comes in from the west through a broad valley. At its mouth 

 is a broad stretch of willow-covered country. Salt River, 22 miles 

 below, is an insignificant stream on the right. The next feature of 

 interest is Birch Island, a large wooded island occupying a dilatation 

 of the river. Gravel River, 8 miles below, is the next tributary of 



Fig. 



G. — Roche Trempe-l'eau, or Rock by the Riverside, Mackenzie River, near Fort 



Wrigley. 



importance." It is a clear-watered stream which forms one of the 

 principal highways for the Indians of the mountains, who descend 

 it in large boats. It approaches the Mackenzie through a broad 

 gravelly Hat, and has a swift current. Below here the river is broad 

 and incloses many wooded islands. At the lower end of this stretch 

 of islands a high bank on the left, with a thick layer of peat on its 

 top, is passed, below which the river is bordered on the left by low 

 banks. The right bank now becomes the higher and continues so 

 nearly all the way to the mouth of Bear River. In one stretch the 

 sandy banks are very high and some stupendous landslips have 

 occurred. The beautiful Hedysarum americanum, the roots of which 



a The name Dahadinne has been applied by authors to both the Rett Rock and 

 Gravel rivers, but is not here used. 



