1855.] 



MURCHISON AND MORRIS THURINGERWALD. 



417 



It must here be stated, though it forms no part of the Thiiringer- 

 wald, that all the lower and undulating region between the eastern flank 

 of that chain and the Erzgebirge is occupied either by Lower Silurian 

 rocks as above defined, or by bands of Upper Devonian and Lower 

 Carboniferous strata. The whole of these rocks, in contrast to the 

 Thiiringerwald, have preserved, to a great extent, a geographical 

 direction from N.E. to S.W., in unison with their original strike. 

 Associated with the Devonian and younger rocks of this large tract, 

 the southern limits of which extend up to the Fichtelgebirge (their 

 northern edges being buried under the Permian rocks of Gera and 

 Posneck), there is, as before said, a great interlamination of contem- 

 poraneous volcanic grit, or ash, which in many parts assumes pre- 

 cisely the form of the " Schaalstein '^ of the Rhine. Besides these, 

 certain eruptive rocks, of posterior date, protrude here and there ; 

 these are quite distinct from the contemporaneous volcanic dejections 

 above mentioned, and the deposits affected by them have been thrown 

 into countless breaks and rapid undulations. In this way, black Lower 

 Silurian slates, with Graptolites and Orthidce, occur in juxtaposition 

 to Upper Devonian. The latter, often expanded to considerable 

 dimensions by the alternation of contemporaneous volcanic materials, 

 and yet containing the same Cypridince and other fossils as at 

 Saalfeld, are, in some localities, surmounted by sandstones, flinty 

 slate, and limestone, charged with the unequivocal fossils of the 

 Carboniferous Limestone; thus removing all doubt respecting the 

 true order. 



With this carboniferous zone terminate, in ascending order, all 

 the formations, which the Germans have hitherto designated under 

 the omnivorous word " Grauwacke ;" i.e.j from the azoic base of the 

 sedimentary rocks to the Millstone Grit inclusive. For all these 

 rocks constitute, in a physical sense, one great mass in Germany, and, 

 to a great extent, in France. They are entirely dismembered from 

 all overlying formations, including the great or Upper Coal-fields of 

 England, — a feature to which we shall again have occasion to allude 

 in speaking of the Harz mountains, and on which we shall offer a 

 general observation or two in our conclusions. 



Fig. 3. — Diagram exhibiting the general relations of the Palaeo- 

 zoic Rocks in Saxony, (chiefly from Naumann.) 



Fleha. 



g. Sandschiefer. "^ 



f ( Zechstein. I 



-' * \ Kupfer-schiefer, &c. J: Permian. 

 e. Rothe-todte-liegende. [ 

 * Plant-beds. J 



d. Upper Carboniferous (Floha and Zwickau). \p • -^ 

 c. Lower Carboniferous (Hainichen-Ebersdorf). J ^^'''"z. 



Devonian. 

 Silurian. 



