2 LI.OYDS NATURAL HISTORY. 



nent, separated therefrom by exceedingly deep water. Instead 

 of largely consisting of ordinary sedimentary rocks, formed in 

 seas of moderate depth, they are in most or ail cases composed 

 of coral or igneous rocks ; and as their fauna and flora are of a 

 totally different type from that of the continents to which they 

 are nearest, it is evident that they have always existed as 

 islands. - , --;/ 



To unite the whole of the British Islands to the Continent 

 would require an elevation of one hundred fathoms at the 

 most ; and that these islands formerly stood at a much higher 

 elevation than is at present the case, we have abundant evi- 

 dence. There occur, for instance, on many parts of our coasts, 

 submerged forests belonging to a comparatively late period, 

 which are now only partially exposed at very low spring-tides 

 after stormy weather, when they are seen to contain stumps of 

 trees rooted in their natural position in the soil, mixed with 

 deposits, containing remains of existing kinds of plants and 

 animals. Such submerged forests occur near Torquay in 

 Devonshire, and Falmouth in Cornwall, as well as on various 

 parts of the coast of Wales, and in Holyhead Harbour. In 

 the case of Falmouth it is estimated that the submergence has 

 been close on seventy feet. Again, on the east coast of Eng- 

 land, at Cromer in Norfolk, we have another submerged forest 

 of older date, which belongs either to the base of the Pleisto- 

 cene, or the upper part of the Pliocene period, and is known 

 as the "forest-bed." Moreover, the occurrence of thousands of 

 teeth of the Mammoth, as well as remains of other Mammals 

 which lived during the Pleistocene epoch, or the one imme- 

 diately preceding our own, on the Dogger Bank, in the North 

 Sea, affords further testimony that this area formed at no very 

 distant epoch a connecting land-link between Britain and the 

 Continent. 



If w^e need further evidence of this subsidence, we have it 



