364 
SILUKIA. 
[Chap. XIV. 
In certain parts, as in the Valdai Hills, the upper beds (represented in the 
following woodcut) are red and green marls, containing several of the above- 
named fossil Fishes of the Old Red Sandstone of Scotland, the whole mass 
being covered by Carboniferous Limestone with its usual fossils, including many 
Producti. 
Ravine of the Belaia in the Valdai Hills. 
(From 1 Eussia-in-Europe,' p. 46.) 
The lower beds, a, b, c, d, e, f, 
consist of various sands and 
marls, in which Ichthyolites are 
disseminated ; but the bed d is a 
complete congeries of Fish-bones, 
surmounted by a copious mass of 
red, white, and green marls. 
Then follow bituminous schists, 
g, k, i, with courses of bad coal, 
constituting the bottom beds of 
the Carboniferous deposits; and 
after other alternations of sands 
and marls, Jc, I, they are followed 
by the Carboniferous Limestone, 
m, n, with many characteristic 
fossils, including even species 
which are well known in Britain, 
such as Productus hemisphjericus, P. punctatus, and P. semireticulatus. 
In the distant region of the Petschora, Count Keyserling obtained satisfactory 
evidence that certain beds charged with Goniatites are inferior to all the other 
Devonian strata of Russia j whilst, as we shall presently see, the chief Goniatite- 
deposit on the banks of the Rhine is underlain by fossiliferous limestone and 
sandstones of great thickness, which there constitute the central and lower mem- 
bers of the Devonian series. 
It seems, indeed, almost certain that there is in Russia no known equivalent 
of the 'Systeme Rhenan ' of Dumont, or great ' Spiriferen-Sandstein,' which forms 
the fossiliferous base of the Devonian rocks of the Rhine *. This inference, 
indeed, is sustained by the fact that the Upper Silurian of Russia is nowhere sur- 
mounted by that band (charged with Cephalaspis and Pteraspis) which consti- 
tutes the lowest member of the Old Red Sandstone of Britain, of the lowest rocks 
of North Devon, and which I consider to be the exact equivalent of the Spiri- 
fer-Sandstone of Coblentz on the Rhine. That the Devonian rocks of Russia 
are completely independent of the Silurian, is therefore demonstrated both by 
their peculiar fauna, and by their reposing in one tract on Upper, in another 
on Lower Silurian rocks, as demonstrated by Helmersenf, Kutorga, Schmidt, 
and others. 
In Poland also, with my associates, I traced true Devonian rocks at and 
around Kielce, to the south of Warsaw, with limestones and many characteristic 
fossils J. These rocks are there followed, on the west, by Carboniferous Lime- 
stones and the thick-bedded Coal-seams which extend from Russian Poland 
into the productive Silesian Coal-field of Prussia. 
* According to M. Barrande, Goniatites occur J See ' Eussia-in-Europe,' vol. i. p. 39. Whilst 
in the Upper Silurian of Bohemia. this edition is printing I have received a memoir 
•f In addition to Helmersen's survey of the De- on the fossils of this Devonian group at Kielce by 
vonian rocks, which extend so largely throughout my old associate in the Carpathian mountains, 
Central Eussia, the late M. Eaimund Pacht also Prof. Zeuschner of Warsaw (Verhandl. Kais. Min. 
described, in some detail, the nature of these Gesells. 2te Ser. vol. i. St. Petersburg, 1866). He 
rocks, and a portion of their fossils, as they occur enumerates twenty species of fossils, all of which 
in Livonia (Devonische Kalk in Lievland. Dor- are known Devonian forms, 
pat, 1849). 
