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CARBONIFEROUS FAUNA OF RUSSIA. 
where, associated with a few other well-known fossils of the system, they almost 
exclusively occupy its upper division; though in another locality’ a few have 
been detected in the middle beds, with Spirifer Mosquensis. 
On the whole, the review of the Carboniferous fauna of Russia indicates nu- 
merous forms which are identical in deposits of the same age in the British Isles, 
North America and Russia; thus affording the strongest proofs, that the condi- 
tions of equable climate which prevailed over enormous areas, during the Silurian 
and Devonian epochs, were continued, in quite as great intensity, during the suc- 
ceeding age. 
As to the bearing of these organic remains upon public utility, we may confi- 
dently say, that by exactly comparing fossils from different and distant localities, we 
have assured ourselves of the precise position of various coal-bearing strata ; and by 
pointing out that the same deposit in one region is entirely void of coal and in 
another is richly charged with that mineral, we have, we trust, helped to solve a 
problem of some national importance. 
