206 



HISTORICAL PALEONTOLOGY. 



marls. The American Trias is chiefly remarkable for having 

 yielded the remains of a small Marsupial (Dromatheriiini), and 

 numerous footprints, which have generally been referred to 

 Birds (Brontozoum}, along .with the tracks of undoubted Rep- 

 tiles (Otozoum, Anisopus, &c.) 



The subjoined section (fig. 139) expresses, in a diagram- 

 matic manner, the general sequence of the Triassic rocks when 

 fully developed, as, for example, in the Bavarian Alps : 



GENERALISED SECTION OF THE TRIASSIC ROCKS OF 

 CENTRAL EUROPE. 



Fig. 139- 



I 



IL It II II I! II ti_ 



I' .. II I! II 



il I II II 



" " I' 



Upper Keuper (Kossen or 

 Rhcetic beds, and Uach- 

 stein beds). 



Middle Keuper (Hallstaclt 

 or St Cassian beds). 



i Lower Keuper (Keuper 

 Sandstones proper). 



Muschelkalk. 



Bunter Sandstein. (Gutten- 

 stein and W erf en beds ?) 



With regard to the life of the Triassic period, we have to 



