VON HAUER INNSPRUCK. 39 



conglomerates, through strata of Tertiary sandstone. Trachytic 

 conglomerates occur around Micheln. A continuous range of basalt 

 (called the Fourteen Mountains) runs betweeu the Zinkenstein and 

 the Planberg. In its deep'^r yjarts, alternations of old basaltic strata 

 with various Tertiary beds may be observed, as also the youngest 

 basalts traversing even trachytes younger than the first basalts. 

 Porphyritic dolerite is met with exclusively on the Letschin Moun- 

 tain. 



The brown-coals of this district are far from being considerable ; 

 four of the beds near Selesel are of superior quality on account of 

 their having been converted into anthracite and native coke by the 

 agency of the basaltic and trachytic eruptions. 



[Count M.J 



On the Geology of the Neighbourhood ©/"Innspruck. 

 By M. von Hauer. 



[Proceed. Imp. Geol. Instit. Vienna, July 1857.] 



The most ancient rocks in the Valley of the Inn, near Innspruck 

 (in the exploration of which M. von Hauer was assisted by M. Foet- 

 terle. Baron Richthofen,and M. Gumbel), are Werfen-slates, cropping 

 out in isolated localities on the west banks of the Inn from beneath 

 the Guttenstein-limestones, which form a continuous zone on the 

 southern slope of the main range north of Innspruck. These are 

 immediately overlaid by the light-coloured limestones, of the main 

 range (INIartinswand, Solstein, Wanger, Levatscher Spitz, &c.), de- 

 signated as " Upper Alpine Limestone * " on the map published 

 by the Tyrol Geological Society, but subsequently proved to be 

 Hallstadt -limestones by their containing Halobia Lommeli, Chem- 

 nitzia Rosthorni, &c. These limestones are overlaid by a marl with 

 the characteristic fossils of the St.-Cassian- and Raibl-strata, and 

 running from Zirl to the Lavatsch Valley, then turning abruptly and 

 continuing through the Hinterau Valley as far as Scharnitz. Above 

 these marls lie extensive masses of dolomite (" Lower Dolomite " of 

 the above-mentioned map), developed into a group of mountains 

 near Seefeld, and which, being immediately covered by Koessen- 

 strata, are considered by M. von Hauer to be of Lower Lias age. 



In the Valley of the Lech, near Warth, Zurs, and Stog (where 

 M. Escher also assisted in the explorations), marly and slaty beds 

 containing Raibl-fossils {Perna Bouei, Hauer, and Corbis Mellingiy 

 Hauer), and associated with much altered and disturbed dolomites, 

 Dachstein-limestones, Koessen-strata, and white and red Adneth- 

 limestones, again make their appearance. [Count M.] 



* See also Quart. Journ. Geol. Soc. vol. x. p. 346. 



