TRIASSIC PERIOD. 433 



2. FOREIGN TRIASSIC. 



The region over which the Triassic rocks outcrop in England 

 stretches across the island from south-southwest, along by the 

 British Channel, to the north-northeast, and also from the centre 

 of this band, along a northwestward course, to Liverpool, and 

 thence north up the west coast, thus dividing England into four 

 parts, — a southwestern (the peninsula of Cornwall and Devon), a 

 southeastern, a western (Wales), and a northern, — indicating the 

 existence of an archipelago of British Isles in the Triassic period. 



In Europe the Trias is found largely developed in regions east 

 and west of the Rhine, from northern Switzerland northward ; on 

 the east side, through Wurtemberg, Odenwald, Thuringerwald, and 

 by Giessen ; and on the west side, along the Vosges, by Strasbourg 

 and Metz, to Aix. The beds occur also in other parts of central 

 Europe, in the eastern Alps, Poland, Russia, Spain, etc. 



I. Rocks : kinds and distribution. 



The subdivisions recognized in France and Germany are three in number: 

 whence the name, from the Latin frier, three. The beds are denominated in 

 these countries and England as follow, beginning with the lowest : — 



I. England. 

 Saliferous beds, or 

 New Red Sandstone, 

 1200 to J 700 feet. 



II. France. III. Germany. 



1. Gres bigarre. 1. Bunter Sandstein, 1200 to 1600 ft. 



2. Calcaire Coquillier. j 2. Muschelkalk, 1000 to 1200 feet. 



3. Marnes irisees. | 3. Keuper. 



In English works the names of the European beds are translated as follow : 

 1. Variegated sandstone; 2. Shell limestone; 3. Red marls or Keuper; — yet they 

 are often written without translation. The names indicate the kinds of rocks. 

 In England they are sandstone and mottled clays (marls), mostly red ; in Europe, 

 near the Rhine, a thick fossiliferous impure limestone lies between a sandstone 

 above and marls below. 



This formation contains the principal salt beds of Europe, and hence it is 

 often called the Saliferous system. The salt in Germany is connected with the 

 middle group, as in "Wurtemberg, where there are noted salt-works. In Vic and 

 Dieuze, France, they are in the upper; and a thickness of 180 feet of rock-salt 

 occurs in the course of 650 feet of rock. The salt layers alternate with clay 

 and gypsum or anhydrite. In England the upper part affords the salt; and at 

 Northwich, in Cheshire, two beds of salt, nearly pure, are 90 to 100 feet thick. 



n. Life. 



The species of fossils in the European Triassic are far more 

 varied and numerous than in the American. The beds have 



