592 STEATIGRAPHICAL GEOLOGY 



Most of these species occur also in the Chillesford Beds, with the 

 addition of Cardium grcenlandicum and Yoldia lanceolata, and 

 most of them are found in the Weybourn Crag, which latter is 

 specially characterised by the incoming of Tellina (Macoma) balthica 

 ( = T. solidula). 



The Norwich Crag has also yielded the following mammalia : 

 Elephas antiquus, Cervus carnutorum, Equus stenonis, Trogontherium 

 Cuvieri (an extinct beaver), Gazella anglica, Arvicola intermedium 



C. BRITISH PLIOCENE DEPOSITS 



The English Pliocene was formerly divided into two groups, a 

 lower and an upper, it being supposed that there was a decided 

 break between the Coralline Crag and the Red Crag, both faunally 

 and physically ; but recent researches have shown that most of the 

 common fossils of the Coralline Crag occur also in the more 

 southern part of the Red Crag, while it also appears that the 

 higher crags to the north of Aldeburgh are quite as distinct from 

 the Red Crag as that is from the Coralline. Hence the series 

 seems to fall naturally into three groups or stages, which may be 

 tabulated as below : 



("Cromer Beds ( = Forest Bed)'! 

 | Weybourn Crag . . | 

 I Chillesford Bee" 

 (.Norwich Crag 



TT vvevDourn ura<c . . , , __ ,. , 



U PP er \ Chillesford Beds f about 20 feet 



( Butley Crag ] 



Middle-! Red Crag^ Newbourn Crag [-combined up to 70 feet. 



{ Walton Crag j 



Lo er /Coralline Crag . . . about 70 feet. 



(Lenham Beds . . . tliickness unknown. 



The Lenham Beds are only found in Kent, and the Coralline 

 Crag only in Suffolk, though in Cornwall there are sands which 

 are probably of about the same age as the latter. The newer 

 crags occupy parts of Essex, Suffolk, and Norfolk, lying unconform- 

 ably either on the London Clay or the Chalk. The only other 

 traces of the Pliocene period in England are a deposit of sand in 

 Dorset containing bones of Elephas meridionalis, 10 and a cave in 

 Derbyshire which has yielded bones of that and other Pliocene 

 animals. 11 In Scotland shells of Upper Pliocene species occur in 

 the Glacial deposits of the eastern coast, and indicate a northern 

 extension of these Crags. 



Lenham Beds. The oldest Pliocene deposits in England are 

 certain patches of ferruginous sand which occur at intervals along 

 the Chalk downs of Kent from the heights above Folkestone to 

 those above Maidstone, most of them being about 600 feet above 



