370 
SILURIA. 
[Chap. XV. 
to numerous mutations of structure, as well as to the dislocations and inversions 
which all the rocks have there undergone, from the Silurian to the Tertiary 
inclusive. 
When, however, we travel westward in a more northern parallel, and pass 
from the central provinces of Russia into Poland, Prussia, and the northern 
states of Austria, we find that, although the Palaeozoic rocks of those regions 
have no longer the wholly unaltered facies which they presented to us on the 
banks of the Neva, the Volga, and the Dwina, and though, unlike their Russian 
equivalents, they have been penetrated by many eruptive rocks, yet they 
contain numerous examples of order and where the normal relations may be 
clearly observed. 
In Poland, and in many low districts of Northern Germany, so widely spread 
are the younger Secondary and Tertiary deposits that the rocks under conside- 
ration rise only in small patches to the surface. Thus, around Kielce *, to the 
south of Warsaw, as before said, Devonian rocks emerge, charged with many 
characteristic fossils, and are followed by Carboniferous Limestone and coal- 
seams that range from Russian Poland into the Silesian coal-tracts of Prussia. 
Thence to the westward, rocks which have been classified as Silurian, Devonian, 
Carboniferous, and Permian occupy detached districts in Prussia, Saxony, the 
smaller states of Germany, large tracts in the northern territories of Austria 
(particularly in Bohemia), and also in parts of Moravia. 
In traversing the Riesengebirge to the south of Breslau, the geologist ac- 
quainted with the full development of the Palaeozoic rocks of other regions is 
struck with the comparative tenuity of the Devonian and Carboniferous deposits. 
In large portions of these mountains (the mineral characters of which have 
been examined in detail by Gustav Rose, whilst their geological distinc- 
tions have been explained by E. Beyrich) the strata of Silurian age have, for 
the most part, undergone a complete metamorphosis. They have indeed passed 
so generally into crystalline schist and marble, that fossils of the earlier era 
have very rarely rewarded the labours of the eminent men above mentioned, 
or of my old friends H. von Dechen and C. von Oeynhausen, who first explored 
that range. That these older crystalline strata are, however, the equivalents of 
the Silurian rocks is certain, because they have been found to contain Graptolites, 
and are clearly surmounted by limestone charged with many Devonian forms. 
In the district of Waldenburg, south of Breslau, and at Silberberg, to the north 
of Glatz, the Devonian limestone, having a thickness of 50 to 60 feet only, is 
charged with Clymenise and many other typical fossils. It is covered by an 
overlying limestone of no greater vertical dimensions, laden with large Pro- 
ducti and several other shells well known in the Mountain-limestone of Britain m 
especially those of the Lower Carboniferous zone, the two beds being separated 
by thin strata of schist. This Carboniferous Limestone is overlain by rocks occu- 
pying the place of the Millstone-grit of English geologists, and which, assuming 
very much the same mineral characters as the rocks whereon they repose (being 
also perfectly conformable with them), were in old times confounded with 
the then undefined 'grauwacke.' It is in this portion of the series, namely in 
the schists and sandstones associated with the Carboniferous Limestone, that 
several of those Plants have been found which Professor Goppert formerly de- 
scribed as of ' transition age' (Calamites transitionis &c). Above these schists 
* See ' Eussia in-Europe,' vol. i. p. 39. mena analoga, St. crenistria (var.), Spirifer line- 
t At one spot, Falkenberg, I collected in the atua, Sp. pinguis, Sp. glaber, with a minute Phil- 
Carboniferous Limestone the following fossils — lipsia, a small Orthoceras, and several species of 
Productus gigas, P. semireticulatus, Stropho- Corals. 
