24 Proceedings of the Royal Irish Academy. 



Mr. Bell to the conclusion that at the period during which these deposits 

 were laid down — that is to say, during the latter part of the Pliocene period 

 — no channel or direct communication existed between the North Sea and the 

 Atlantic Ocean, the Straits of Dover being closed in the south, while in the 

 north the Tertiary volcanic chain formed a barrier across from the north of 

 Scotland to Greenland by way of the Shetland Islands, Faroes, and Iceland." 



Mr. Eeid's contention that the St. Erth beds are older than Messrs. Kendall 

 and Bell estimated — that they are, in fact, of early Pliocene age — is founded 

 chiefly on the circumstance that the percentage of extinct species is about the 

 same as that of the Coralline Crag. The consideration of the supposed 

 climatic conditions does not seem to me of any particidar value ; and, as he 

 remarks, the exact age of the clays is still doubtful.' Even if the St. Erth 

 beds belong to the lower Pliocene, there are no grounds for the supposition 

 that the northern barrier, alluded to by Messrs. Kendall and Bell, had ceased 

 to exist in later Pliocene times. 



The change in the Pliocene fauna of the east coast of England, as we pass 

 from the older to the newer beds, no doubt implies, as Mr. Harmer pointed 

 out, an opening up of the area to the influence of the northern seas.' But 

 we do not possess the slightest evidence for the assumption tliat the Atlantic 

 Ocean was similarly aflected. Many of the facti, indeed, lead to the 

 conclusion that the land on the Atlantic coasts of the British Islands stood 

 highest in late Pliocene and early Pleistocene times, and that it was then 

 that Hdix liortcnsis and many other European species must have made their 

 way to America. 



Glacial conditions prevailed at this time on all the high mountain ranges 

 surrounding the warm Atlantic Ocean, and yet the coast region must have 

 supported an abundance of animal and plant life. The presence of a land- 

 bridge between Scotland and North America by way of Greenland, and 

 another between England and France, would have excluded the Gulf Stream 

 from the Arctic Kegions. Professor Blytt's argument that under such 

 conditions all the coast region, including Iceland and southern Greenland, 

 would have had a higher temperature than at present, while the lands beyond 

 were probably colder, seems irrefutable.' Yet Professor James Geikie believes 

 that even the latter countries would then have had a more genial climate.' 



In my opinion it was during this epoch, in Pre-Glacial times, that the 



' KenUI, P. F., an.l K. Bell, " The Pliocene Beds of St. Brtb." pp. 20C, 207. 



' Beid, C, " Pliocene Deposits of Britain," p. 61. 



' Harmer, J. W., " Pliocene Deposits of QolUnd," p. 754. 



* Blytt, Abel, " Tbeorie d. veduelnden KUm&tf," p. 49. 



' Geikie, James, " Prehistoric Eorape," p. 520. 



