1863.] MURCHISON PERMIAN OF BOHEMIA. 30f> 



In Germany, as in Britain, there are two zones of the Carboni- 

 ferous group, each of which has been clearly described by Geinitz. 

 The lower of these, which Professor Sedgwick and myself showed, in 

 the year 1839, to be of the age of our Mountain-limestone, has been 

 elevated with, and is conformable to, the Palaeozoic rocks (Devonian 

 and Silurian) beneath it, — a phenomenon which ranges, indeed, 

 through Germany and France. The other, or overlying, coal-field, 

 like that of Bohemia and Saxony, is quite unconformable to the lower, 

 and is also quite unconnected with the base of the Permian, — it 

 having been clearly shown by Geinitz that its surface was abraded 

 before the lowest portion of the Roth-todt-liegende was deposited ; 

 whilst the latter formation contains within it rolled fragments, 

 derived from the uppermost coal-strata in the environs of Dresden. 

 It is thus proved that the Permian group is independent of all the 

 subjacent Palaeozoic rocks, as established by stratigraphical and palae- 

 ontological data. 



In concluding this sketch of the Permian rocks of Bohemia, let me 

 add a remark or two on the physical and geological conditions under 

 which these deposits may have been accumulated. Unlike the Per- 

 mian rocks of Northern Germany and England, the conglomerates, 

 sandstones, shales, marls, and limestones which constitute the so- 

 called Roth-liegende of Bohemia are not overlain by the Zechstein 

 with marine shells. Nor, as in Russia, do we meet with alternations 

 of deposits which were unquestionably marine with others which, from 

 their plants and some of their included remains, were probably of 

 lacustrine and terrestrial characters, showing rapid alternations of 

 level. 



That portion of the Bohemian deposits which is most richly charged 

 with fossils has, from the character of its imbedded animal remains, 

 been referred by Geinitz to a freshwater origin. But if it be granted 

 that the small lizards which formed the impressions called Saurich- 

 nites are of terrestrial origin, is it settled that all the Fishes which 

 have been enumerated lived in fresh water ? I confess that on this 

 head I am very sceptical, after seeing what has transpired respecting 

 the fishes of the Old Red Sandstone of Scotland, which for a time 

 were believed to have lived in fresh water, but which in Russia have 

 been found associated with unquestionably marine shells. Leaving, 

 however, naturalists to settle these points by some direct working- 

 out of the true affinities of these fishes, I may state that my friend 

 Sir P. Egerton is of opinion that the Palceonisci were probably fishes 

 that lived in estuaries. On this point I would observe that, after all, 

 these Bohemian ichthyolites do not differ essentially from those of 

 the copper-slate of Northern Germany, which constitutes the natural 

 base of the Zechstein, just as the marl-slate is the bottom of the 

 purely marine Magnesian Limestone of England. Now, what if, 

 in this great development of Permian strata in Bohemia, the upper 

 red marls and sandstones of considerable thickness, which there 

 overlie the bituminous and cupriferous schists with Fishes, should 

 be found to contain a few sea-shells like the red Permian marls 

 at Manchester, and of forms like those in the Zechstein ? Why, then 



