CHAP. XII.] ICENIAN PERIOD. 251 



of early Pliocene deposits from the intermediate area can- 

 not be held as a very serious objection to the view that 

 they communicated across the Hampshire basin. That the 

 Diestian or Coralline Crag sea had some very direct com- 

 munication with the Mediterranean and west European 

 area is indicated by the large proportion of Mediterranean 

 species among its mollusca, namely 200 out of the 265 

 living species, or 75 per cent., 17 of them being now con- 

 fined to the southern area ; it is difficult to see in which 

 direction this connection could have existed if not through 

 England and France. 



It is generally supposed that the Anglo-Belgian sea of 

 this period opened northward into the Arctic Ocean, but 

 this belief is doubtless founded upon the present extension 

 of the German Ocean, which is really more likely to have 

 been initiated in the later part of what we call Pliocene 

 time. I cannot find, indeed, that there is any good reason 

 for supposing the sea of the Coralline Crag to have stretched 

 far north of Suffolk. In fact, the total absence of any signs 

 of Coralline Crag or of the box-stones in Norfolk, and the 

 manner in which the lower and older portions of the newer 

 crags thin out northward and westward in that county, 

 are significant facts which incline me to believe that Nor- 

 folk at any rate did not form part of the early Pliocene sea- 

 floor ; in other words, that the Coralline Crag was deposited 

 in a gulf which lay wholly to the south of Norfolk, and 

 was limited by a promontory of land which stretched out 

 north-eastward from Norfolk far into what is now the North 

 Sea, if it did not reach entirely across to the shores of 

 Norway and form a complete barrier between the Anglo- 

 Belgian sea and the Arctic Ocean. 



The mere presence of some twelve or fourteen species 

 which have now a northern, i.e. Arctic or Scandinavian, 

 habitat, cannot be taken as proof that there was any con- 

 nection with the Arctic sea, for these species may then have 



