Results of a Second Geological Survey of Russia. 01 
part the fossils of the white chalk of Europe, such as the Inocerami Rear 
tillus), Belemnites mucronatus, Ostrea vesicularis, Ter ebratula carneas 
Above the cretaceous system, we have not been able to discover in any 
part of Russia, except in the Crimea, the “nummulite limestone” which 
there scts on, and acquires, a great importance in its range through Georgia, 
Egypt, and the Mediterranean basin. 
The equivalents of the lower tertiary formations (Eocene of Lyell) scem 
to exist in one part only of your country (S. of Saratof). On the other 
hand, the middle and upper tertiaries (Miocene and Pleiocene) cover 
large surfaces on the Lower Volga, in Podolia, Volliynia, and also along 
the shores of the Sea of Azof and the Black Sea, mace the youngest of 
these strata, very much resembling the ‘upper crag” of Norfolk, are 
beautifully displayed. 
I have not time to enter upon the numerous and interesting phenomena 
of the Ural Mountains, the examination of which occupied us nearly three 
months. We there studied alternately the wonders of the gold alluvia, 
the sites of the entombment of your great mammalia, and sought for the 
causes of the astonishing metamorphism of the sedimentary rocks of that 
chain. For an explanation of the last class of phenomena, the works 
of Humboldt and Gustaf Rose must always be consulted. I will on this 
occasion simply say, that far from being primitive, as was supposed, this 
chain, with the exception of its eruptive masses, is entirely composed of 
Silurian, Devonian and Carloniferous rocks, more or less altered and cry- 
stallized, but in which nevertheless we have been able to recognise in a 
great number of localities my own Pentamerus Kniyhtiit, and many fossils 
which clearly define the age of the other strata. These rocks, though 
much broken up, are arranged in parallel bands, the mean direction of 
which in the North Ural is from N. and by W. to 8. and by E., whilst 
in the South Ural, trending N. and §., they assume a fan-shaped arrange~ 
ment, spreading out towards the southern steppe of the Kirghis, where, 
interlaced with porphyries and other trap-rocks, they are often converted 
into the far-famed jaspers of this region. 
Still less can I now pretend to treat of the great carboniferous region 
of the Donetz ; for without entering into details concerning this southern 
tract, so valuable to the future interests of Russia, I cannot render it 
the justice which it merits. Still I may say to you as a geologist, that its 
numerous beds of coal (bituminous and anthracitic), with its grits and 
shales, are completely subordinate to the mountain Jimestone series, and 
represent in no sense the coal-fields of Great Britain, Belgium, and France. 
* After this letter was written, we found in the collection of Professor Eichwald, 
at St Petersburgh, a fine specimen of Exogyra and other fossils in a green sand- 
stone from the Lower Volga, sent to him from a locality well known to us, which 
leaves little doubt of the existence also of a true representative of our greens 
sand,—R. I. M. 
+ Silurian System, p. 615. 
