THE EOCENE. 591 



THE TERTIARY PERIOD. 



We now enter upon a period when the animal creation attained its 

 greatest development, the "Age of Mammals"; for they were then the 

 kings of creation. The Tertiary Period is divided into three stages, viz. 



The EOCENE, or the Dawning of the now existing" creation. 



The MIOCENE, or the Middle, or "minority" of existing creation. 



The PLIOCENE, or the Recent, or still more developed period. 



We will glance at them in that order which Sir C. Lyell introduced. 



The Eocene formation is shown in what is termed the "London Basin," 

 here illustrated by a section in which we find soft sands without fossils 

 (Thanet Beds), and a kindred kind in Surrey, in which fossils (marine) are 



Fig. 680. Skull of the Dinotherium. 



found. After these we get the "Reading and Woolwich" beds as we 

 ascend. These are of clay and pebbles, etc., with river fossils. The 

 Oldhaven beds are included on the map ; they occur towards Blackheath 

 and Herne Bay. The London clay is very stiff, and in some places blue. 

 It is full of fossils of birds, beasts, fruits, and vegetables, trees, reptiles, and 

 fish, and the variety of the organic remains appears to indicate the fact that 

 at one time the Thames flowed through swampy ground to the sea, in which 

 dwelt, in a warm climate, immense mammalia, such as the megatherium, 

 glyptodon, tapir, etc., and some turtles of enormous size. 



It is also on record from late observations that these immense animals 



