Ixiv PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



in the N.E. Alps, read by M. v. Hauer before the Imperial Geo- 

 logical Institute of VienDa, at the close of 1853, he has gone into 

 great detail on these formations, some portions of which, as refer- 

 ring to this question, I will here briefly allude to. The author com- 

 mences by dividing the Triassic group of the N.E. Alps into two 

 formations : 1 . The Werfen, and 2. the Hallstadt. The first or lowest 

 of them he again divides into — a. the Werfen slates or variegated sand- 

 stones, and b. the Guttenstein limestone, which he considers as pro- 

 bably equivalent to the Muschelkalk. Ke considers the Hallstadt 

 strata as upper Muschelkalk. I may here remark that the author has 

 excluded from this Triassic group the Dachstein limestone, which he 

 had formerly considered as lower Muschelkalk, and has placed it as the 

 lowest member of the overlying Liassic group. As far as the order of 

 superposition is concerned,this correction appears, from the subsequent 

 investigations of others, to be perfectly correct. But it is not equally 

 certain that he is correct in placing the Dachstein limestone in the 

 Lias. With regard to the Werfen slates, the author states that all 

 recent inquiries have confirmed the correctness of the position origin- 

 ally assigned to them, viz. that they immediately overlie the Grau- 

 wacke beds, and underlie the whole of the Alpine limestone. The 

 principal fossils found in them are. Ammonites Cassianus (Quenst.), 

 Turho recticostatus (Hauer), Naticella costata (Miinst.), Myacites 

 Tasserensis (Wissm.), very common, Myophoria, sp. unc, Posidono- 

 inya Clara (v. Buch), Posidonomya aurita (Hauer), Avicula striato- 

 punctata (Hauer), Av. Venetiana (Hauer). The Ammonites Cas- 

 sianus is of rare occurrence, and it may be a question whether it has 

 not been derived from the overlying Dachstein ; for it is a remarkable 

 fact, that one of the causes of the apparent intermixture of fossils in 

 some of these Alpine collections, particularly those of S. Casciano, 

 has arisen from the fact of their having been obtained from rivulets 

 which descend through Jurassic as well as Triassic deposits. These 

 Werfen slates are constantly overlaid by dark grey limestones, called 

 by the author Guttenstein limestone or Muschelkalk, and frequently 

 assume the form and character of Bauchwacke limestone. Fossils 

 are almost unknown in them, with the exception of Ammonites (or 

 Ceratites) Cassianus (Quenst.) and Monotis Salinaria. The upper 

 portion of this limestone is occasionally dolomitic, and passes into 

 the second or upper subdivision of the Triassic group. 



The Hallstadt Limestone or upper Muschelkalk is remarkable for 

 its beautiful and curious Cephalopods. The author here explains 

 that his recent investigations have led to the conviction that his 

 former statements respecting the position of the Dachstein limestone, 

 which he had placed below the Hallstadt limestone, required correc- 

 tion : the sections found by M. Siiss and himself in various parts of 

 the Alps showed that the Dachstein Limestone should be placed 

 above that of Hallstadt. With regard to the Cephalopods, which 

 constitute the greater portion of the fossils found in this formation, 

 the author refers to a distinct memoir in which they are described ; 

 the new forms discovered since the publication of that work will be 

 published in the 2nd vol. of the Transactions of the Imperial Geolo- 



