12 GEOLOGICAL MEMOIRS. 



of Duppau and of the Mittelgebirge by their outburst broke the con- 

 necting link between the Erzgebirge and the Carlsbad Mountains, 

 and caused it sink to a lower level. The first tertiary deposits 

 covered the flattened mountain-tops, the succeeding ones were 

 deposited in the basin formed by the breaking down of the older 

 rocks. Traces of this catastrophe may be seen in the violent dislo- 

 cations of the lower lignitiferous deposits, and in the great precipices 

 existing around Carlsbad. 



[Count M.] 



On the Mountain Limestone and Old Red q/* Britain. 

 By Prof. De Koninck. 



[Proceed. Imp. Geol. Instit. Vienna, Feb. 19, 1856.] 



M. von Hauer communicated a letter from Prof. De Koninck, in 

 which he states that he has succeeded in tracing in the Carboniferous 

 formation of England and Scotland two quite different faunae, the 

 one corresponding to the carboniferous fauna of Vise and Bleiberg, 

 the other to the fauna of the Tournay coal-basin. These two faunae, 

 although contemporaneous, are nowhere found co-existent. 



Prof, de Koninck thinks that the Old Ked Sandstone of England 

 and Scotland, supposed to belong to the Devonian system, is in 

 reality the base of the carboniferous group ; a circumstance without 

 analogy in the rest of Europe. 



[Count M.] 



Additional Information respecting the Mayence Tertiary 

 Formation. By Prof. Frid. Sandberger. 



[Leonhard und Bronn's Neues Jahrbuch fiir Min., &c. 1856, pp. 533-536.] 



M. Weinkauff, of Kreutznach, has forwarded to me for exami- 

 nation the fossils which he continues to collect from the coarse- 

 grained marine sand of that neighbourhood. The sand is generally 

 cemented together by barytes. Although these fossils are merely 

 casts or impressions, often consisting of pure barytes, they can 

 nevertheless be accurately determined chiefly by comparison with the 

 well-preserved remains of Weinheim and Alzey. The following list 

 will show that the result gives a much greater abundance of species 

 than was hitherto suspected, as well as local divergences from Wein- 

 heim, particularly in the abundance of several species. Moreover 

 two specimens of Cerithium margaritaceum were for the first time 

 found in the lowest bed of the basin, this fossil being one of the most 

 common in the upper bed. Altogether I have found the following : — 



Fossil-wood and Cones, both derived from Coniferce. 



Corals, identical with the Thecosmilia found in badly preserved fragments 



at Weinheira. 

 Ostraea callifera, Lam., generally Pecten furfuraceus, A. Braun. 



smaller than at Alzey. Chama exogyra, A. Braun. 



Pecten pictus, Goldf. Pectunculus crassus, Phil. 



