39 
The Carboniferous series is found in the northern and central portions of Rus¬ 
sia, but only the lower or calcareous beds occur, with sandstone, bituminous shale, 
and thin beds of impure pyritous coal, with the usual vegetable remains of coal 
measures. These are overlaid by a limestone somewhat similar to the British 
magnesian limestone, and sometimes resembling pisolite, while another is white 
and not much more compact than the calcaire grassier of Paris, 
This white producta limestone stretches to the distance of a thousand miles. It 
has been called by some chalk, to which it bears a resemblance in containing no¬ 
dules of flint, (chert'?) sometimes coated with corals. With this are associated 
immense beds of gypseous alabaster; and thin bands of limestone alternate with 
it, which has been determined to be, from its fossils, the true mountain limestone 
of the coal measures. No workable beds of coal can be expected to be discovered 
south of Moscow. 
Oolitic series.—It had long been a matter of doubt whether a series of strata 
could be found to connect the lower carboniferous beds with certain rocks of the 
oolitic series which were known to exist in the south of Russia. Some of those 
beds which rest on the great red formation along the banks of the Volga unques¬ 
tionably belong to the middle oolite, as they contain the ammonites and belemnites 
identical with those belonging to that order. Some of the shells, however, resem¬ 
ble the lias; and on this point Mr. Murchison reserves his opinion till comparisons 
can be made of the fossils. The shales of the oolite rest directly on the white car¬ 
boniferous limestone of Moscow. 
Ferruginous sands cover the lias. In these are found large concretions of grit 
used for mill-stones, but no fossils as yet have been discovered in them. 
Chalk .—The cretaceous system is very extensive, but was not on this occasion 
particularly examined. 
Tertiary deposites .—Such deposites have not been discovered in the northern 
or central regions of Russia. 
Younger Pliocene , (Pleistocene.)—-Before the visit of these gentlemen, it was 
supposed that all the great masses of superficial detritus were referable to the dilu¬ 
vium epoch, in which the remains of the great extinct quadrupeds were also im¬ 
bedded. They had not the leisure, however, to make a thorough examination of 
this interesting subject, but they were satisfied that it was divisible into several 
ages. They discovered as many as fifteen or sixteen varieties of shells of modern 
species. Mr. Lyell confirms this, and identifies them with the Udda-valla group. 
This demonstrates that, at a modern period, the whole of the vast flat country of 
Russia was under water, and the eastern shores of the sea extended to the foot of 
the Ural Mountains. 
Drift and Erratic Blocks .—All the older formations are covered with detritus, 
the large granitic boulders of which, with the pliocine which they had discovered, 
were all derived from the north. This subject they intend to make the matter 
of a separate work. 
Mr. Lyell spoke of the great importance of these discoveries in removing doubts 
as to the new arrangements of the British rocks, especially in reference to the iden- 
