Trof. H. Carvill Lewis — Comparative Studies in Olaciation. 29 



Whether it stopped among the mountains or in the lowlands, its 

 edge was approximately outlined by unusual accumulations of drift 

 and boulders, representing the terminal moraines. As in America, 

 this outer moraine was least distinct in the lowlands, and was often 

 bordered by an outer fringe of drift several miles in width. 



South of an east and west line extending from Tralee to Dungarvan is 

 a non-glaciated zone free from drift. Several local systems of glaciers 

 occur in the south of Ireland, of which by far the most important is 

 that radiating from the Killarney mountains, covering an area of 

 2000 square miles, and entitled to be called a local ice-sheet. Great 

 glaciers from this Killarney ice-sheet flowed out of the fiord-like 

 parallel bays which indent the south-westernmost coast of Ireland. 

 At the same time the Dingle mountains, the Knockmealdown and 

 Comeragh mountains, and those of Wexford and Wicklow furnished 

 small separate glaciers, each sharply defined by its own moraine. 



No evidence of any great marine submergence was discovered, 

 although the author had explored the greater part of Ireland, and 

 the eskers were held to be phenomena due to the melting of the 

 ice-sheet and the circulation of subgiacial waters. The Irish ice- 

 sheet seemed to have been joined at its north-eastern corner by ice 

 coming from Scotland across the North Channel. All the evidence 

 collected indicates that a mass of Scotch ice, reinforced by that of 

 Ireland and England, filled the Irish Sea, over-riding 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 observations of the Irish geologists and of 

 the author were combined, in which was shown the central sheet, 

 the five local glacial systems, all the known strise, and the probable 

 lines of movement as indicated by moraines, striae, and the trans- 

 port of erratics. 



The glaciation of Wales was then considei'ed. Wales was shown 

 to huve supported three distinct and disconnected local systems of 

 glaciers, while at the same time its extreme northern border was 

 touched by the great ice-lobe 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 Brecknockshire Beacons. The glaciers from 

 each of these centres transported purely local boulders and formed 

 well-defined terminal moraines. The northern lobe, bearing granite 

 boulders 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 Carnarvon- 

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

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

 Welsh mountains. This great moraine, filled with far travelled 

 northern erratics, is heaped up in hummocks and irregular 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 



