ScHAUFF — On the Origin of the Eurojyean Fauna. 491 



ones to the east and centre. They, indeed, still occupy the tracts 

 where they originally arrived in the country. Had all the animals 

 and plants reached the island from the south-west, where the sunken 

 land is supposed to have been situated, that part would probably be 

 the richest in species, whilst it is in reality much the poorest, and 

 nothing strikes a naturalist more forcibly than the absence there of a 

 large number of the commonest Irish species. 



Let us take an example from the mollusca. Pour species of Helix, 

 belonging to the subgenus Xerophila, inhabit Ireland, viz. Helix vir- 

 gata, H. intersecta, S. erieetorum, and S, larlara {acuta). They rarely 

 make an attempt to hide themselves, are 

 extremely conspicuous, and always occur 

 in abundance wherever found. They 

 inhabit almost the whole of Ireland, but 

 are especially common round the coast. 

 For some years I have carefully collected 

 statistics as to their occurrence, and have 

 specially visited many parts of the coast, 

 and have invariably found one or more of 

 the four species ; but the only strip of 

 coast-line in Ireland where they are com- 

 pletely absent is that between Yalentia 

 Island and Baltimore — that is to say, all 

 along the Kenmare River and Bantry 

 Bay — the very coast |where we should 

 expect them to occur plentifully if the theory of their survival on the 

 southern sunken land were correct. As they presumably entered 

 Ireland from the east, and then travelled both inland and along the 

 coast, it must be surmised that they have not yet been able to colonize 

 the extreme south-west. 



That the whole Irish fauna and flora could have survived on a 

 now sunken southern extension of Ireland is, therefore, impossible. 

 They must have remained within the present boundaries of the island 

 during the Glacial Period, though it is probable that it did extend 

 somewhat more to the west, south, and north, then it does now, and 

 that those parts of the countiy stood at a relatively higher level to 

 the east ; so that the Shannon and some other rivers, which now 

 drain into the Atlantic, emptied their waters into the Irish Sea 

 (see 76a). 



The nature of the Pleistocene Mammalia of Eastern England is not 

 such as to lindicate an Arctic climate in the British Islands. The 



E.I.A. PKOC, SEE. III., VOL. IV. 2m 



' . — Map of Ireland on which 

 the distribution of the Xero- 

 philous Helices is indicated 

 hy dots. 



