202 Pfoceedings of the Royal Irish Academy. 



The dramlins to the north of the line Ballyshaunon-Belleek are largely 

 composed of schist and not of carboniferous limestone, though the mounds 

 rest immediately on the latter, and well within its boundary. This peculiar 

 distiibution was long ago noted by Maxwell Close, who recognized its 

 significance of a westerly transportation. These gneissic or metamorphic 

 boulders, derived from the triangular area of Pre-Cambrian rocks, decrease as 

 traced seawards, the carboniferous limestone fragments increasing simul- 

 taneously, until finally, in the neighbourhood of Ballyshannon, the drifts are 

 almost exclusively charged with boulders of the local carboniferous rocks. 

 At Eossnowlagh, the diifts so well exposed in the upper and receding parts 

 of the sea difls and in the railway section also consist chiefly of carboniferous 

 rocks, together with boulders of schist, diorite, and well-rounded gianit«. 



Striae furnish corroborative evidence of this east-west motion of the ice, 

 though cross striations (E. by S., and E. 3^. E.\ first noted by Maxwell Close, 

 along the railway circa two miles east of Ballyshannon, may suggest that the 

 direction was subject to slight variation at different times in correspondence 

 with changes in the relative pressures of the component streams. 



On the barren carboniferous limestone moorland, north-east of Bally- 

 shannon, but few striated surfaces were observetl. In the area north-west of 

 Pettigo, striae and drumlins are fairly numerous, their orientation indicative 

 of ice-motion to the south-west. Lakes abound, but of these few only are 

 true roek-basins, most being held up by drift, usually in the form of 

 drnmlinoid moimds. The latter have impounded such lakes as Lough Aniarla, 

 and the loughs of Path and Ballyalla. Other lakes again are entirely 

 surrounded by turf, and seem to be merely small hollows in the turf moors, 

 though probably also primarily due to irregular deposition of drift. 



Lough Eske is most probably a ' Zungenl^ecken,' though its origin must 

 be partly ascribed to solution of tlie underlying limestone. Even the floor of . 

 the great amphitheatie in which the lake rests may have been considerably 

 deepened and lowered by glacial erosion, whose severity is borne out by the 

 numtonn4e surface. The drift where exposed is seen to be a very stony 

 accumulation, consisting chiefly of carboniferous rocks, with some schist, 

 quartz, and granite. To the east of Lough Eske the drift is a sandy, yellow, 

 or brown clay, charged with boulders of these schist, granite, and 

 carboniferous rocks, while the sandy nature of the matrix is to be attributed 

 to the disintegiation of the two rocks last named. The members of the 

 carboniferous become increasingly ai^llaeeous as they are traced southwards ; 

 this lithological change is reflected in a con-esponding change in the character 

 of the drift, which to the south of Lough Eske becomes much tougher in 

 consistency, and darker in colour. 



