ESCHER VORARLBERG. 



21 



according to M. Heer, by the anthracite, extending in the French, 

 Savoy, and Swiss Alps as far as Mont Todi, is not represented in the 

 Vorarlberg and the country to the south. It re-occurs in the Stang- 

 Alp in Styria. It is probable therefore that, at the period when the 

 carboniferous rocks were deposited in the districts where they now 

 occur, the Vorarlberg formed an island, the dimensions of which it 

 is difficult to determine. The researches of M. Escher are not 

 equally conclusive as to whether it was land at the Permian epoch 

 and during the commencement of the Trias. At the period of the 

 formation of the St. Cassian beds and the Lias, however, the district 

 had long been covered by the sea. 



The absence of strata more modern than the Lias and Dolomite 

 indicates that since the deposition of these the surface has remained 

 uncovered by the sea. The terrestrial area of the period in question 

 extended on the west about as far as where the Rhine now flows ; since 

 further in that direction the Jurassic rocks occur in full development. 

 To the south it extended to the borders of Lombardy ; in fact, there 

 are not found anv fossils younger than the liassic between the central 

 Grisons, the Lake Como, and the Valley of Camonica. The south- 

 ern limit is difficult to fix. 



In the western part of Switzerland, as far as the Lake of Lucerne, 

 there has been no violent dislocation between the Jurassic and the 

 Cretaceous groups, these being parallel in their disposition. The 

 passage from the Cretaceous to the Eocene has also been tranquil. 

 The absence of Eocene beds in the Chain of the Vorarlberg and the 

 Sentis makes it appear that at the Nummulitic epoch there was in 

 this region an archipelago, the islands of which were distributed in a 

 totally different manner to the existing arrangement of the mountain- 

 tops of the region, observation having shown that most of the sum- 

 mits of the highest limestone-range of Switzerland, from the Todi to 

 the Wildhorn, are formed of nummulitic rock. 



Between the deposition of the Flysch and that of the Molasse 

 there was a disturbance of the surface which converted the chain of 

 the Alps into a continental region ; a condition which prevented the 

 Molasse from being deposited in the interior of the Chain ; this fact 

 was recognized long ago. Lastly, the most recent, and perhaps one 

 of the greatest of the revolutions that have affected this region, is 

 that which took place after the deposition of the Upper Freshwater 

 Molasse (which is upraised at Saint- Gall, on the borders of the Lake 

 of Zurich, and at the Scbnebelhorn), and before the formation of 

 the Lignites of Uznach, Diirnten, and Aix-en-Savoie. If, however, 

 M. C. Meyer, by his researches, definitely classes the Marine Mo- 

 lasse as Miocene, and connects it on one side with the Molasse of 

 the South of France, and on the other with the tertiary Vienna basin, 

 there still remains some doubt as to the exact age of the Upper 

 Freshwater Molasse, which has a thickness of not less than 1000 

 feet. 



The mammalian remains found in the three stages of the Molasse 

 do not denote any difference of age ; and the researches of M. Heer 

 indicate such minute differences, that he is disposed to regard the 



