296 NEOZOIC TIME. [CHAP. XIII. 



Plate XIV. I have taken the line of 80 fathoms (480 feet) 

 as the extreme limit, though it does not make much 

 difference with respect to the extent of the land which line 

 is taken. As stated already, the river flowing through 

 the North Sea was the Ehine, the Thames, Ouse, and all 

 other British rivers which now flow into that sea being its 

 tributaries. 



The English Channel was a wide valley through which 

 the united waters of the Seine and Somme, with many 

 tributaries from southern England, ran westward to the 

 Atlantic. The Bristol Channel was a similar valley watered 

 by a continuation of the river Severn, and opening west- 

 ward on to a vast plain which lay to the south of Ireland. 

 Thus Professor Dawkins, alluding to a cave on Caldy 

 Island off the coast of South Wales, in which numerous 

 remains of large mammalia have been found, remarks, 

 " It may, therefore, be reasonably concluded that when 

 they perished in the fissures Caldy was not an island, but 

 a precipitous hill overlooking the broad valley now occupied 

 by the Bristol Channel, but then affording abundant 

 pasture. We must, therefore, picture to ourselves a fertile 

 plain occupying the whole of the Bristol Channel, and sup- 

 porting herds of reindeer, horses, and bisons, many ele- 

 phants and rhinoceroses, and now and then being traversed 

 by a stray hippopotamus, which would afford abundant 

 prey to the lions, bears, and hyaenas inhabiting all the 

 accessible caves, as well as to their great enemy and de- 

 stroyer Man." 



St. George's Channel and the Irish Sea formed another 

 large area of low-lying ground, the centre of which, as 

 already mentioned, was occupied by a long but compara- 

 tively narrow lake ; this lake received the waters of all the 

 rivers which drained the surrounding parts of Ireland, 

 Wales, England, and Scotland, and the Admiralty charts 

 show that the excurrent river ran from its southern 



