202 THE FOREST LANDS OF NORTHERN RUSSIA. 



devoid of all indications of life. With the strata super- 

 imposed upon them it is otherwise, and at this point 

 the subject is taken up by Count Saporta in the paper 

 cited. 



Above the azoic strata are superimposed the Silurian, a 

 designation originating with Sir Roderick Murchison, 

 derived from Silures, the name of an ancient tribe which 

 inhabited a district of country between England and 

 Wales, in which the rocks so designated are very distinctly 

 developed, but a deposit which is very widely diffused; 

 the Devonian, so named because it happens to be very 

 extensively preserved in Devonshire, but which also is 

 very widely diffused, and is known also as the Old Red 

 Sandstone, in contradistinction to a later formation desig- 

 nated the New Red Sandstone ; the mountain limestone, 

 so called in contradistinction to cretaceous and chalk 

 deposits of a later date ; and carboniferous strata, otherwise 

 known as the coal measures, which are generally found 

 superimposed upon, but sometimes alternating with, 

 deposits of the mountain limestone. 



In reference to the great extent of azoic strata, gneiss, 

 and crystalline schists, during the deposit of which the 

 water still covered extensively the earth, Count Saporta 

 alleges that the ocean did not then present conditions 

 requisite for the support of animated structures even of the 

 lowest order ; that it must have been only in the sea, when 

 reduced to a temperature which, though still high, would 

 not coagulate albumen, that such could be expected to 

 appear ; that this appearance would occur in basins com- 

 paratively calm, suitable for the development and subse- 

 quent maintenance of such organisms ; that there is 

 nothing known at variance with the supposition of BufTon 

 that this must have occurred first in proximity to the 

 Pole ; and, moreover, that there terrestrial vegetation first 

 appeared, when vegetation first ceased to be exclusively 

 aquatic, and appeared on land still immersed in vapours, 

 and bathed by the tidal wave ; and he goes on to say : 



* In these the earliest formations must have been humble 



