350 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 5, 



the north of my geological map. The blue and grey marly limestones 

 contain numerous and well-preserved specimens of 



Ammonites amaltheus, Schlth. 



Ammonites Nodotianus, B'' Orb. (also found at Adneth). 

 Ammonites radians, Schlth. 



Ammonites Reussi, Hauer. Similar to Am. Humphreysianus, 

 Sow., but with very different lobes. 

 Ammonites Partschi, Stur. 

 Ammonites tatricus, Pusch. 

 Inoceramus ventricosus. Sow. 



These Lias strata dip with very steep angles, being nearly vertical 

 to the south, and are evidently in a very irregular position. They 

 lie conformably on enormous masses of sandy and marly Flysch 

 rocks, which extend to the north, and contain immediately under the 

 Lias strata (which in their mineralogical characters are often scarcely 

 to be distinguished from them) nothing but many specimens of the 

 Fucus intricatus. 



Above the Lias strata is found a small zone of dolomite, dipping 

 everywhere at 70° and 75° to the south, or south 70° west. Ascend- 

 ing the slopes of the Sonnenberg, we find a thickly-wooded declivity, 

 above which begin the sandstones of the chalk with Orhitulites, but 

 dipping with quite an opposite direction to the north. 



B. Lias and Jura on the Hirschbiihel and the Wetterstein. 

 Under the designation of " Upper Lias and Jura," I have laid down on 

 the map two separate zones of strata ; the one in the Lahnewiesgraben, 

 the other on the southern foot of the Wetterstein. In both localities 

 are found strata of marl and limestone, in general of a red or of 

 greyish and greenish colour. Amongst the many fragments of fossils 

 I had collected, there could be determined with accuracy only 



Ammonites radians, Schlth. In small specimens. 



Ammonites tatricus, Pusch. 



Aptychus, similar to A. lamellosus, but recently distinguished from 

 it by M. Schafhaiitl under the name of A. siibalpinus. They occur 

 very often in the contorted red marly limestones of the Lahnewies- 

 graben, but not in the "Wetterstein. 



Accordmg to the order of superposition of the strata, this forma- 

 tion is evidently situated, as seen in the Gaistha], between the inferior 

 Lias and the upper Alpenkalk. 



The above-quoted fossils might indicate them to belong either to 

 the Lias or to a higher Jurassic group. I have comprised these 

 strata on the map under the collective name of "Lias and Jura," 

 since I expect that further investigation may possibly lead to a sepa- 

 ration of these strata into two distinct groups. 



If we follow out the distribution of these strata on the geological 

 map, we find that in the Lahnewiesgraben their eastern prolongation 

 is stopped by a very remarkable transgressive position of the dolomites 

 of the Kramerberg, of which we shall speak hereafter. On the 

 Wetterstein it is very difiicult to trace accurately the limits of the 

 western and eastern prolongation of the band of the Lias and Jura 

 strata. Large masses of debris and the difficulty of traversing the 



