Russia and the Ural Mountains. 533 
told, that this vast group is composed of limestones, marls, great 
masses of gypsum, rock-salt and repeated alternations of cupriferous 
strata; and that it contains a flora and a fauna of characters inter- 
mediate between those of the Carboniferous and Triassic periods. 
The shells are, to a great extent, those of our Magnesian Limestone 
or Zechstein; and, like the conglomerate of that deposit near Bris- 
tol, the Permian rocks are distinguished by the presence of The- 
codont Saurians. The interest attached to these vast deposits, which 
have been spread out on the western flanks of the Ural Mountains, 
is increased by the inferences which have been drawn, that springs 
and currents holding much copper in solution must have flowed 
from the edges of that highly mineralized and metamorphic chain, 
while the Permian strata were accumulating. But the great value 
of having worked out a fuller and richer type of a group of strata 
between the Carboniferous and Triassic epochs than any which 
exists in Western Europe, will be found in the fossil shells, the plates 
of which are already far advanced; for, with some species hitherto 
known in the Zechstein of Germany and Magnesian Limestone of 
England, we shall publish others which are identical with or analo- 
gous to forms that occur in rocks occupying the same geological 
position in North America, of which I will speak hereafter, and 
concerning the age of which great doubts had prevailed. 
In America, indeed, as in Russia, these beds had been compared 
with every deposit, from the coal to the Keuper inclusive, whilst in 
our work they will be shown to have no connection with the New 
Red Sandstone or Triassic group, but to occupy a definite position, 
truly intermediate between that system and the carboniferous. At 
the same time it is manifest, that although they overlie and are, as 
they ought to be, very distinct from the Carboniferous system, yet 
they contain some species of shells which occur in that division. 
Thus it will be made evident, that after all there now remains scarcely 
any real difference of opinion on this head between Mr. Phillips and 
myself (to which I alluded last year); for I learn from him, that in 
England the analogy between the fossils of the Magnesian and Moun- 
tain Limestone obtains to a far greater extent than could be supposed 
from any published catalogues. I trust, therefore, that the ensuing 
year will not be without its fruits in the production of new works 
on the shells of the Magnesian Limestone of our own country ; and 
I am glad to have it in my power to inform you, that Mr. King, the 
Curator of the Natural History Society of Neweastle-on-Tyne, is 
preparing some excellent materials for this purpose. 
A better acquaintance with the Permian fossils, particularly the 
prevalent Mollusca, induces me, notwithstanding the arguments I 
employed last year, to infer that this deposit, so naturally connected 
through its characteristic fossils with the Carboniferous strata, must 
be classed with the Palzozoic rocks*. The physical structure of 
Russia is also greatly in favour of this view; for, in large portions of 
that country, there is an entire absence of the great rupture between 
* My companions, M. de Verneuil and Count Keyserling, have long en- 
tertained the same views as Mr. Phillips on this point. 
