366 
SILUEIA. 
[Chap. XIV. 
The clearest proofs are thus exhibited (the two formations being quite con- 
formable) that the portion of the series which is very slightly coal-bearing in 
Devonian and Carboniferous Bocks in the Gorge op the Tchussovaya River 
(West Flank op the Ural Mountains). 
(From ' Russia-in-Europe and the Ural Mountains,' vol. i. p. 386). 
Central Russia, and much more so on the Donetz, is entirely wanting on the 
flanks of the Ural. 
These Carboniferous Limestones, everywhere more or less characterized by 
their Producti, are overlain along the western edge of the Ural chain by sand- 
stones and grits which occupy much the same place in the general series as the 
Millstone-grit of England. In that region, indeed, coal has been worked on 
the banks of small affluents of the Tchussovaya*, near Ust Coiva and other places, 
in a representative of the Millstone-grit (see 1 Russia-in-Europe,' vol. i. p. 126). 
In Russia, however, these strata are often more calcareous, and contain Go- 
niatites. They constitute the uppermost bands of the Carboniferons group, 
properly so called, in the vast territory between the Volga and the Ural Moun- 
tains, where they are seen in many localities to be at once succeeded by the 
Permian deposits before described. These, the highest Carboniferous beds in 
Russia, contain only at intervals thin coal-seams ; and the great Upper Coal- 
measures of England have no representative in the Russian Empire. 
* From the recent writings of Helmersen it appears that these coal-beds have been much opened 
out since I visited these tracts, and that the mineral has been discovered at various places along the 
upper flanks of the Carboniferous Limestone on the Tchussovaya. 
