308 Dr, Hayden on the Period of Elevation-of the 
there is a belt of country 800 to 600 miles in width, where, for 
the most part the only timber to be seen, is a thin fringe border- 
ing thestreams. Even in the eastern portion of the main range, _ 
the timber is not luxuriant, like that so common along the coast — j 
of Oregon and California. The pine trees are seldom more than 
three feet in diameter. : . 
Again, we may divide the mountains or elevated ridges which 
form the different ranges into two kinds; viz., those with long 
extended lines of fracture, with a granitic nucleus and a compar- 
atively regular outline, and those which appear to be com 
of a 
Series of cones or peaks more or less intimately connectet 
% 
portion of No. 1, or the Dakota group, whic 
Cretaceous epoch in this portion of the West, is comp 
