THE FAUNA OF BRITAIN. 123 



in Ireland of the pre-glacial fauna is somewhat 

 difficult to accept, considering that we have such 

 undoubted evidence of a very extensive submergence. 

 The case of Isle of Man, quoted by Mr. Carpenter, 

 can be met, I think, by the supposition that it was 

 connected with Cumberland until quite recently, and 

 quite independently of any connection between Eng- 

 land and Ireland; that the Isle of Man, in fact, 

 was always a cape or peninsula of the mainland, and 

 only recently became separated by local subsidences 

 or by the action of the sea. 



Part of the history of the British fauna will be 

 referred to again in the next chapter, which deals 

 with the Arctic migration. We need not therefore 

 dwell any longer on this subject here. There is one 

 matter, however, which is of importance in connection 

 with the geographical conditions of the British Islands 

 at the time when the greater portion of our fauna 

 arrived from abroad. 



On page 60 will be found a map indicating the 

 physical geography of that part of the ancient con- 

 tinent on which what are now the British Islands were 

 situated. Only one large river has been marked on 

 that map, namely, that flowing out of a lake which 

 occupied part of the Irish Sea. Another probably dis- 

 charged its waters into the Atlantic midway between 

 France and England, whilst the Thames may have 

 been a tributary of the Rhine, as it emptied itself 

 into the sea near our south-east coast. I have shown 

 in a previous essay that the former presence of a fresh- 



