504 REPORT—1883. 
carboniferous age. This conclusion does not invalidate the correctness of Murchison’s 
classification for the strata of the Permian region proper; though it must be borne in 
mind that during last year Mr. Twelvetrees showed, both in the ‘ Geological 
Magazine’ and in a paper read before the Geological Society, that further south, 
in the Orenburg country, a true Dyassic facies, as it is understood in Germany, 
can be recognised; the Rothliegende (with some subordinated limestones, as in 
Germany) being succeeded upwards by a true Zechstein formation, the latter being 
overlain conformably by a series of cupriferous marls and sandstones (‘ Upper 
Permian’ of Murchison). The data given by Mr. Twelvetrees are all in favour 
of the view which regards these marls and sandstones as a transition series between 
the Dyas and Trias, which very nearly coincides with the views expressed by 
M. Jules Marcou at the time when Murchison’s ‘Permian System’ was first 
propounded, Reference is also made to the transition series of Giimbel, which 
occurs in Southern Tyrol, described by the author in a paper on the Triassic Deposits 
of the Alps in the ‘Geological Magazine,’ November 1882, and in his Report to the 
British Committee of the International Geological Commission. In both of these 
papers the general equivalence of the English Post-carboniferous and the German 
Dyas is pointed out, reasons for such a conclusion having been given in the earlier 
papers more at length. The term ‘ Permian’ has therefore only a local and 
subordinate value, and scarcely applies even to the whole Russian area in which 
these strata are developed. 
This summer the author has spent some time at work upon the German and 
Austrian series of Post-carboniferous rocks, and has had the able assistance of 
Dr, Von Hauer, Professor Geinitz, Professor Liebe, and others. The main pur- 
pose of the present communication is to bring forward new facts bearing upon the 
relation of the Dyas and Trias of Central Europe. These facts have been gleaned 
(1) from a study of the collections of the Geologische Reichsanstalt of Vienna; 
(2) from a recent communication to the Jsis in Dresden by Professor Geinitz, 
containing a description by Hr. A, Dittmarsch of the extensive erosion of the 
Upper Zechstein (Plattendolomit) at Ostrau, in Silesia; (3) from a series of 
quarries near Meerane in Saxony, which the author (at the suggestion of Pro- 
fessor Geinitz) has lately visited, and in which the unconformity of the lowest 
Bunter strata (Murchison’s ‘ Bunterschiefer’) with the Zechstein is most pro- 
nounced and unmistakable (sections were described) ; (4) from a week’s work in 
Northern Thiiringen, where, both in detail and on a larger scale, the break in the 
stratigraphical sequence of the Dyas and Trias is shown to be absolute and 
complete. The German terminology (Dyas and Trias), which was first established 
on a consideration of their organic remains, is thus fully confirmed by physical and 
stratigraphical evidence, and the idea of a conformable sequence of the Bunter 
upon the Zechstein, which has been so strongly insisted upon by Murchison and his 
collaborateurs, is shown to be a fiction. From which it follows that the application 
of the ‘ Permian System,’ as propounded by Murchison, to the Post-carboniferous 
rocks of Central Europe is no longer tenable, any more than is its application to 
the British series, as the author has shown elsewhere. 
6. On the Coloration of some Sands, and the Cementation of Siliceous 
Sandstones. By the Rev. A. Irvine, B.A., B.Sc., F.G.S. 
In the first part of this paper attention is drawn to the occurrence of certain 
ereen-coloured sands which are frequently met with below the peaty layers, at the 
heads of the small valleys, in the Upper Bagshot sands. The local and exceptional 
nature of these green deposits, and their relation to the decomposing vegetal 
matter which has overlain them for a long period of time, suggest the connection 
of the green colour with the decomposition of vegetation. Chemical analysis of 
these sands shows that the green colour is in no way connected with any of the 
ordinary green minerals which enter into the formation of rocks, but reveals the 
organic origin of the colouring matter. For details of this, reference is made to 
papers by the author, one read before the Geologists’ Association, the other in the 
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