THE TRIAS. 



585 



Fig. 671. Plesiosaurus. 



the deeply-laid granite or limestone was lifted to the summits of the 

 mountains from the depths of the sea. Land and water came and went, 

 and the ever-changing earth still 

 brought forth abundantly " the herb 

 yielding seed after its kind," and 

 the " moving things upon the 

 ground after their kind," ever im- 

 proving and developing till they 

 culminated in the splendid vege- 

 tation and immense animals of the 

 Tertiary period, and lay silent after- 

 wards in the cold grasp of the 

 great ice age for the thousands of 

 years of the glacial epoch. 



We now enter upon the TRIAS, 

 or New (Upper) Red Sandstone, 

 which is divided into Upper and 

 Lower Trias, "Keuper" and "Bun- 

 ter." We have three principal headings in the Secondary System the 

 TRIASSIC (the oldest), the OOLITIC, and the CRETACEOUS. In the first we 

 find red sandstones and shelly limestone ; in the second, clays and shale ; 

 in the last, chalk, or white limestone. In some districts there are traces of 

 volcanic action. 



On the top of the " Upper Trias," or " Keuper" formation, we have the 

 Lias, which succeeds the Rhaetic beds, and in this we find many rich traces 

 of reptiles and birds which come now before us in the rising scale of creation. 



In the seas of this period we 

 have numerous Crustacea, the 

 nautilus and ttte cuttle-fish. 

 The Saurians now come before 

 our retrospective vision. It is 

 the " Reptile Age" in all its 

 development, and the huge 

 labyrinthodon, the iguanodon, 

 pterodactyle, and ichthyosau- 

 rus testify to the magnitude 

 of the fauna of the period. 

 The first mammal specimen, 

 a marsupial, has been traced 

 back to this time ; and the 

 tropical temperature was 

 favourable for luxuriant vege- 

 tation, pines, and palms. 

 In the swamps or shallow waters the great reptiles disported themselves, 

 and seized their prey, the water-fowl, which now appeared in numbers, and 



