72 EARLY MAN IN BRITAIN. [CHAP.IV. 



by the waves on the submergence of that part of the 

 Pleiocene land. 



The British Pleiocene strata 1 are divided into the 

 following groups. 



Newer Pleiocene of Lyell. Feet. 



Westleton beds ) ^ . 



Chillesford Clay. } Manne ' 



Aldeby beds, j 



Norwich Crag > Fluvio-Marine . 20 



(Mammalia). I 



Older Pleiocene of Lyell. 

 Red Crag \ 



Phosphatic or ... Marine . . 20 ? 



coprolite beds, j 

 Coralline Crag { . 



(Polyzoa). } Marme ' 



Geography of Britain in the Pleiocene Age. 



The Pleiocene coast-line of Great Britain is marked 

 by the marine deposits above mentioned in East Anglia, 

 which were accumulated by the sea that swept over the 

 district to the east of a line passing from the mouth 

 of the Thames to Colchester and Ely, and extended in 

 the direction of Holland and Belgium as in the Meio- 

 cene age (Fig. 10). 



The North Sea, which was small in the Meiocene age 

 (Fig. 6), and did not touch our present coast-line, was 

 now gradually enlarged at the expense of the land, and 

 ultimately a direct communication was made with the 

 Arctic Sea, by the sinking of the land extending from the 

 Scandinavian mountains and the British Isles to Iceland 

 and Greenland on the one hand, and Spitzbergen on the 

 other. This depression is proved by the presence of 

 northern types of marine shells as far south as the coasts 



1 See Prestwich, QuaH. Journ. Geol. Soc. Lond. xxvii. pp. 115, 325, 452. 



