TRANSLATIONS AND NOTICES 



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GEOLOGICAL MEMOIRS. 



On the Equivalents of the "Kossen Strata" in Suabia. 

 By Dr. A. Oppel and M. E. Suess. 



[Proceedings Imp. Acad. Vienna, July 1856.] 



A well-developed group of secondary rocks has been observed in the 

 Eastern Alps, subsequently to the discovery of the organic remains 

 of the St. Cassian beds. The series has a palseontological character 

 of its own, differing in that respect from any other sedimentary 

 formation hitherto known. 



The group in question may be divided into two sub-groups, 

 distinctly separated from each other by the nature of their organic 

 remains, although conformable in stratification (as far as at present 

 observed) and equally affected by the powerful upheavings of sub- 

 sequent periods. Each of these sub-groups has, in certain localities, 

 a thickness of several thousand feet ; both of them are of purely 

 marine origin ; and limestones greatly predominate in both. 



The inferior deposit, to which belong the beds of St. Cassian and 

 Hall in Tyrol, the Ilallstadt beds in Upper Austria, the deposits of 

 Esino in the Lombardian Alps, and of Raibl in Carinthia, are now 

 known to contain about 800 species of organic remains, not one of 

 which is found anywhere beyond the East Alpine territory. 



The superior deposit, comprising the Kossen beds in Tyrol, those 

 of Starhemberg and of Kitzberg near Pepnitz in Lower Austria, of 

 Bellagio on the Lake of Como, of Scesaplana in the Vorarlberg, and 

 of the Stockhorn, together with the whole calcareous deposit known 

 as " Dachstein Limestone," is admitted by the Austrian geologists 

 to be more nearly connected with the Lower Lias than is the lower 

 sub-group of Hallstadt and St. Cassian. The Swiss naturalists, how- 

 ever, think that this Kossen group should be united with the lower 

 sub-group under the common denomination of St. Cassian Formation ; 

 the separation lying, as they suppose, not below, but above the Kos- 

 sen Beds. This question having no influence on the opinions regarding 

 the stratigraphical order of the deposits, we may now set it aside ; and, 

 in order to prevent any misunderstanding, we intend to use the terra 

 " Cassian Strata" for the lower sub-group exclusively. 



No strata exactly concordant in palaeontological characters with 

 those in question having been found among the marine deposits of 

 Western Europe, German and other naturalists have acquiesced in 

 the opinion that the chronological equivalents of these deposits were 

 to be sought for elsewhere, in the Keuper strata deposited in shal- 

 lower water. This hypothesis still wants more proofs, on account of 

 the totally discrepant physical circumstances under which the Keuper 



VOL. XIII. PART II. B 



