7 22 Proceedings of the Royal Irish Academy. 



Assuming that the land stood at its present level when the ice-sheet 

 dissolved, it is probable that sufficient material would have been left 

 behind, when the ice melted, to choke up practically the whole of the bay 

 and convert it into dry land. But even if we eliminate the part played 

 by the glacial drift in elevating the floor of the Clew Bay basin, it is 

 clear that at a subsequent date, with the laud standing above its existing 

 level at the minimum height proved by the present position of the 

 submerged peats and forests, the submarine ridge above referred to would 

 rise well above the sea, and form a land-connexion between Clare Island and 

 the mainland. 



