Rev. A. Irving — Triassic Deposits of the Alps. 495 



category of the Palaeozoic rocks : the notion of their comprehension 

 in this great series precedes therefore, and guides, our apprehension 

 of the meaning of the term as it is here used. 



The main object of this paper is to draw attention to some of the 

 latest results obtained by workers in Alpine geology, so far as they 

 apply to our series : the results of the observations made by Giimbel, 

 von Ilauer, Mojsisovics, Emmerich, Zittel, Theobald, Pichler (not 

 to mention others), should be better known than they are to the 

 majority of English geologists. Maps published only a few years 

 ago, in which a great portion of the limestone strata of the Alps was 

 comprehended under the general name of ' Alpenkalk,' a name with 

 which one is familiar in Cotta's " Die Alpeu " (a highly suggestive 

 work), and other writings of that period, are now practically obsolete 

 for purposes of geological observation. 



Post-Carboniferous [Dijassic) Strata. — On the northern side of the 

 great east-and-west crystalline axis of the Alpine chain observations 

 hitherto made seem to have failed to detect the presence of any 

 very extensive deposits which can be referred to this system : the 

 Triassic strata (according to von Hauer) follow at once upon highly 

 metamorphosed rocks of Silurian age.' Von Hauer, however, includes 

 certain deposits (Verrucano, etc.) among the Triassic strata, a proviso 

 which must be borne in mind in comparing this statement with the 

 dark streak which represents these deposits on his Map of Tirol, 

 indicating their intervention between the crystalline and stratified 

 series in N. Tirol. Further, a glance at the excellent Map of 

 Switzerland by Studer and Escher von der Linth shows that, with 

 the exception of these Verrucano deposits here and there, the Jurassic 

 strata as a rule immediately succeed the crystalline rocks of the 

 Central or Swiss Alps. In the southern zone the deposits thus far 

 observed, which appear to be of Post-Carboniferous age, are com- 

 prehended also under the term ' Verrucano.' This may be defined 

 as a series of grey and red-brown conglomerates and breccias, with 

 red sandstones, and here and there coal-bearing strata. Von Hauer 

 refers these to the lowest horizon of the Trias, but admits that they 

 may with equal propriety be considered (in part at least) as belonging 

 to the age preceding the Trias : Griimbel goes further, and recognizes 

 in them the Alpine equivalents of the Kothliegende of Germany. 

 The latter writer also points out that in places (e.g. in the Gailthaler 

 Gebirge) limestone-strata containing marine fossils occur, which he 

 considers to be comparable with the Zechstein, or at least with 

 " strata recognized as of Dyassic age in the Nebraska region of 

 North America." ^ 



Accepting then the place assigned by Giimbel to the Verrucano 

 and its associated deposits, we see that, as in the German and Eng- 

 lish areas, so in the Alpine area (or more correctly that portion 

 of the earth's surface now occupied by the great Alpine mountain- 

 system) the age of the Eothliegende was characterized by enormous 



1 Vide descriptive text of the Geologische Uehersichtskarte der Oesterreichischen 

 Monarchie, Blatt No. 5, by Dr. Franz Eitter von Hauer. 



2 Anleitimg zu Geol. Beobachtimgen in den Alpen, von G. "W. Giimbel. 



