Geological Society. 49 



within a certain limited district, between Kehlheim on the S.E. and 

 Pappenheim on the N.W.j to pass upwards into a slaty, compact 

 limestone, which is exposed in plateaux overlying dolomitic Jura 

 kalk on both banks of the river Altmiihl, but is of sufficiently 

 fine texture, in only a few quarries near Solenhofen, to be worked as 

 lithographic stone*. The quarries are then described, and their 

 fossil contents, as collected by the author or observed by him in the 

 collections of Count Miinster and others, are enumerated. Seeing 

 the prevalence of Pterodactyli, Insects, Crustaceae, and Tellinites, 

 and knowing that these fossils, together with certain plants, are 

 also found in the Stonesfield slate of England, and further that these 

 slaty beds at Solenhofen immediately surmount limestones, which 

 by their contents are found to be the equivalents of the middle and in- 

 ferior oolites of England on which the StonesBeld slate also rests— he 

 is led to consider it probable that the Solenhofen and Stonesfield 

 slates are of similar age ; an opinion which he believes has been re- 

 cently expressed by Dr. Boue. 



The whole of this slaty group of Solenhofen, &c. is seen near the 

 mouth of the Altmiihl to thin out between masses of dolomite ; the 

 whole being surmounted by green-sand and cretaceous deposits. 



The author inclines to the opinion that the higher members of the 

 oolitic groups of England, viz. Coral Rag, Portland Stone, &c., have 

 not yet been defined in any part of central Germany, though they 

 may exist in Hanover ; and' he is unable to say whether the limestone 

 of Nattheim, Heidenheim, &c., so abundant in corals, is referrible to 

 the upper part of the great oolite or to the coral-rag. 



Green Sand. — It is remarked that wherever this formation shows 

 itself in Germany, it is nearly always divisible, as in England, into 

 lower or siliceous sandstone, and upper or cretaceous sandstone ; 

 the former known in certain districts as the quader sandstein, the 

 latter as the planer kalk. Numerous sections exhibiting these two 

 formations are given in various parts of southern Hanover and the 

 northern flank of the Hartz, where the lower sandstone is sometimes 

 an highly ferruginous rock, at others a white sandstone, in which 

 character it ranges from the northern flank of the Hartz into Saxony 

 and Bohemia. In Westphalia the green-sand series is said to ap- 

 proach still closer to the mineral type of the English group, and sec- 

 tions are described near Bidofeld, Soest Weil, &c. in which not only 

 an up))er and a lower green-sand with many characteristic fossils are 

 described, but also traces of a separating stratum of blue marl or gault. 

 ChaUc.—The author states that the chalk is quite as clearly sepa- 

 rated from the planer kalk in Hanover, as the chalk of the South 

 Downs is from the malm rock or upper green-sand in Western Sussex. 

 He remarks that on the northern flank of the Ilartz, Professor Sedg- 

 wick and himself observed it to be quite vertical, wliilst the under- 

 lying green-sands were by great faults thrown uj) into unconformable 

 juxtaposition ; and he further refers to a memoir recently read by 

 himself, in which the chalk with flints is stated to occur in southern 



* For a specific account of this range, sec Von Buch's Letter to IJrong- 

 niart, 1823. 



N.S. Vol. 10. No. 55. July 1831. H Bavaria, 



