AND TRIAS OF CENTRAL EUROPE. 401 
Middle and Lower Zechstein by the Upper Rothliegende being in that 
region, according to Geinitz, the usual order of things*. All through 
Triassic and Jurassic times, however, a large part of Central Kurope, 
of which we may regard Bohemia as the centre, was elevated above 
the sea: and it is only when we come down to later Cretaceous 
times that we find evidence of the sea again spreading over the 
Bohemian main-land. An example of this sequence of things is seen 
in the neighbourhood of Dresden. In the Plauenscher Grund the 
Rothliegende is found overlying the productive Coal-measures, and 
both of these lie against the flank of the syenite massif of that 
district. Immediately upon the Rothliegende lie rocks of Cretaceous 
age, consisting of Greensand, Quader Sandstein, and Pliner Sandstein. 
From this sketch, which can be verified by a reference to Von 
Dechen’s map of Germany, it would appear that it is more than a 
mere hypothesis upon which the present speculation rests ; while in 
the Geologische Reichsanstait at Vienna the same great break in the 
succession of the Bohemian strata is shown by the remains of the 
flora exhibited from the Coal-measures upwards to the Cretaceous 
rocks. 
This ancient Bohemian district which may be considered par 
excellence the Cambria and Siluria of Central Europe, has probably 
never been wholly submerged since 1ts elevation in post-Carboniferous 
times. In later Cretaceous times, however, a partial subsidence of 
the region permitted the intrusion of marine waters over great 
portions of the country which now are occupied by the basins of 
Vienna and Bohemia. What is especially important to note here is 
the prevalence during Triassic times of true marine conditions over 
the area now occupied by the Hastern Alps fT with their various rami- 
fications, and extending far away (how far it is impossible perhaps 
to say) to the south of this central Kuropean Cambrian and Silurian 
land-area; while continental conditions, as represented by the 
Bunter and Keuper formations, extended to the west and north of 
the same region, with an interlude represented by the Muschelkalk, 
when the marine conditions which prevailed to the south all through 
Triassic times were extended northward, though never so far as 
the British area. The feebler accentuation of the facies of the 
Muschelkalk as a distinct marine formation towards the north and 
west in the German area may be considered as a well-established 
fact of European geology?. 
The crystalline rocks of the Black Forest, against and around the 
eroded flanks of which the Triassic rocks lie, are probably another 
remnant of the great east-and-west barrier which has been described ; 
* See ‘ Fuhrer durch das k. mineralogische Museum in Dresden,’ p. 64. 
+ Ido not mean to say there was then no land in the Hastern Alpine area. 
Our President, Prof. Bonney, has lately shown reason for believing in a con- 
siderable elevation of the crystalline rocks of the central chain prior to Triassic 
times (‘ Nature,’ vol. xxx. p. 45); and there is enough difference between the 
Triassic strata and their included organic remains, on the north and south of 
the Alps, to show that they were not deposited in one and the same, although 
in connected, areas (Geol. Mag. Dee. ii vol. ix. pp. 499, 500). 
t Vide Credner, ibid. p. 497,{and the table, pp. 502-505. 
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