CHAP. VL] PLEISTOCENE FORESTS IN FRANCE. 131 



The sands and red marls forming No. 5 owe 

 their singular contortions and foldings probably to the 

 grounding of large masses of ice, as well as to the sub- 

 sequent melting of ice on which some parts of them had 

 been originally deposited. The Forest-bed of this section 

 is to be seen along the coast of Norfolk and Suffolk from 

 Cromer as far as Pakefield, where it has been protected 

 by the thick covering of sands and clays seen in the 

 section, from the denuding forces, by which the traces of 

 both forest and animals have been removed from other 

 parts of Britain. Close on the destruction of the forest 

 followed the depression of temperature marked in the 

 lignites, No. 3, which arrived at its maximum in the 

 period of the boulder drift, No. 4, when the area was 

 invaded by icebergs. This was accompanied by a con- 

 siderable geographical change. The North Sea rolled 

 over both forests and lignites, and had become sufficiently 

 deep, in Norfolk and Suffolk, to allow of icebergs deposit- 

 ing their burden to form the covering of boulder clay 

 resting on the lignites and fluvio-marine strata. 



Early Pleistocene Forests in France. 



The forests of France, according to the recent inves- 

 tigations of the Count de Saporta, 1 present a regular 

 series of changes in the Meiocene, Pleiocene, and Pleisto- 

 cene ages, the tropical species gradually and succes- 

 sively retreating farther to the south. Under the present 

 climatal conditions the species of fig-tree, known as 

 Ficus carica, essentially a southern form, is not found 

 farther north than 45 in central France, except under 



1 Congrts Internationale $ Anthropologie et Archdologie Prfhistorique 

 Stockholm, 1874, p. 80. 



