. 
3 
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G. M. Dawson— Geology of the Peace, River Region. 398 
have yet been found in this region, though it is probable that 
they occur on the Peace below the confluence of the Smoky. 
The lithological resemblance of the shales of the Upper and 
Lower sub-divisions to those of the Pierre and Benton sub- 
divisions is exceedingly close. It is probable that these mark 
periods of general submergence, when sediment-bearing cur- 
rents passed freely through the interior continental valley. 
Elevation is known to have been in progress during the Nio- 
the interior continental region. 
The fossils of the Lower or Dunvegan sandstones are of 
overlaid by one thousand feet of strata containing Cretaceous 
types of fossils, a little group of forms, presenting such modern 
affinities that, if placed before any paleontologist unacquatn- 
ted with the facts, they would be at once referred to the 
Tertiary,” 
In the Peace River district we find, instead of a merely 
local intercalation of this kind, a widely-extended series of 
Cretaceous age, persistently holding fresh-water and 
estuarine types of mollusks and land plants. _ 
‘he chief evidence going to prove the Tertiary age of the 
Laramie and Fort Union beds, after that afforded by the plants, 
* U.S. Geol. Survey of Territories, 1872, p. 435. 
Am, Jour. copay ns eee Vou. XXI, No, 125.—May, 1881, 
