THE EUEOPEAN SEAS. 



219 



Iceland, which has the winter temperature of 

 North Cape, has also its Arctic assemblage of Mol- 

 lusca. 



The Baltic area experiences a degree of winter 

 cold far below that of the portion of the external 

 coast, corresponding to it in latitude. At the upper 

 end of the Gulf of Bothnia the temperature is that 

 of the Arctic coast ; in the Gulf of Finland there 

 is the cold of Cape North. Such are the low tem- 

 peratures affecting the brackish waters of the 

 northern portion of this internal sea, and which 

 may in part account for the poverty of its fauna 

 as compared with that of the southernmost half. 



Crossing the whole European area, the great in- 

 ternal brackish seas of the Aral and of the north 

 Caspian, have winter temperatures corresponding 

 with those of the Arctic Ocean. 



It is from about Bergen and the southern parts 

 of Norway and Sweden that the assemblage of Mol- 

 lusca and other marine animals had been obtained 

 which form wdiat has been termed the " Boreal " or 

 " Scandinavian fauna." This section of the western 

 coast of Europe, with a somewhat higher winter 

 temperature, shows a wonderful increase in the 

 numbers of the component members of its fauna. 



The whole of the group of the British Islands, 

 our internal seas, and both coasts of the English 

 Channel, come within a winter temperature of from 

 40° F. to 32° F. ; such is the winter cold of the 



