﻿of North America, Great Britain and Ireland. 435 



No evidence of any great marine submergence was discov- 

 ered, although the author had explored the greater part of Ire- 

 land, and the eskers were held to be phenomena due to the 

 melting of the ice and the circulation of subglaeial waters. 

 The Irish ice sheet seemed to have been joined at its northwest- 

 ern corner by ice coming from Scotland across the North Cnan- 

 nel. All the evidence collected indicates that a mass of Scotch 

 ice, reinforced by that of Ireland and England, filled the Irish 

 Sea, overriding the Isle of Man and Anglesey, and extending 

 at least as far south as Bray Head, south of Dublin. A map of 

 the glaciation of Ireland was exhibited in which the observa- 

 tions of the Irish geologists and of the author were combined, 

 and in which were shown the central sheet, the five local glacial 

 systems, all the known strise, and the probable lines of move- 

 ment as indicated by moraines, strise and the transport of 

 erratics. 



The glaciation of Wales was then considered. Wales was 

 shown to have supported three distinct and disconnected local 

 systems of glaciers, while at the same time its extreme northern 

 border was touched by the great ice sheet of the Irish Sea. The 

 most extensive local glaciers were those radiating from the 

 Snowdon and Arenig region, while another set of glaciers 

 radiated from the Plinlimmon district and the mountains of 

 Cardiganshire, and a third system originated among the Bren- 

 ockshire Beacons. The glaciers from each of these centers 

 transported purely local bowlders and formed well-defined ter- 

 minal moraines. The northern ice lobe, bearing granite bowlders 

 from Scotland and shells and flints from the bed of the Irish 

 Sea, invaded the northern coast, but did not mingle with the 

 Welsh glaciers. It smothered Anglesey and part of Carnar- 

 vonshire on one side, and part of Flintshire on the other, 

 and heaped up a terminal moraine on the outer flanks of the 

 north Welsh mountians. This great moraine, filled with far- 

 traveled northern erratics, is heaped up in hummocks and irreg- 

 ular ridges and is in many places as characteristically developed 

 as anywhere in America. It has none of the characters of a sea- 

 beach, although often containing broken shells brought from 

 the Irish Sea. It may be followed from the extreme end of the 

 Lleyn Peninsula (where it is full of Scotch granite erratics), in 

 anortheasteily direction through Carnarvonshire past Moel Try- 

 fan and along the foot of the mountains east of Menai Strait to 

 Bangor, where it goes out to sea, re-appearing farther east at 

 Conway and Colwyn. It turns southeastward in Denbighshire, 

 going past St. Asaph and Halkin Mountain. In Flintshire it 

 turns southward and is magnificently developed on the eastern 

 side of the mountains, at an elevation of over 1000 feet between 

 Minera and Llangollen, southwest of which place it enters Eng- 



