THE TRIAS. 121 



conglomerates and sands, which are usually 

 white, but sometimes red. There are some evi- 

 dences that its upper beds were denuded before 

 the overlying alternations oi marls and sandstones, 

 named the Keuper beds, were deposited. Tl. 

 divis >onding to the 



upper and lower divisions of the Trias in ( iermany, 

 ; which theshell limestone, termed Muschel- 

 kalk. s, yielding numerous marine fossils, 



and many peculiar fossil reptile-. 



- attain a thickness in Lancashire 



. Cheshire Of 5200 feet. The Keuper is there 



s the Bunter ; but in Leicester and 

 Warwickshire the a] te thickness of both di- 



of the I 3 than 1000 feet ; and of 



as about one-tenth. 

 - a southern thickening of the Trias in 

 I I leVOn, where the ved rocks 



are well 1 the coast, and are about 2500 



feet thick. Th w or no fossils in the 



Bum 



s tit of Cheshi hiefly in the 



marl in two principal bed North- 



h of the principal lenticular masses 



ibout 100 feet thick. (ivpsiim is also 



found in the marls, and is largely worked in Staf- 



The occurrence of the salt may be 



attributed to the evaporation of an inlet of the 



that the process was substantially the 



ie as that now going on in the salt-pans on the 

 •f the Mediterranean, where salt is obtained 

 artificially by evaporation of sea-water. There 

 appear to have been many of these ancient salt- 

 pans. The lower bed at Morthwich is about three- 

 quarters of a mile in diameter. The salt has been 

 preserved by the marl in which it is contained, 



