290 Scientific Proceedings, Royal Dublin Society. 



parallelism of its fragments destroyed. Tongues of marl, from a 

 few inches to a foot broad and up to sixteen feet long, penetrate 

 into the head from east to west. Lenticles of head are separated 

 from the main mass of the deposit, and lie contorted and drawn 

 out in the marl. The red upper clay does not appear to be 

 present always, in which case the marl weathers to a brownish 

 clay, which contains few stones, and sometimes exhibits blue joints. 



In the middle of the bay, at a small break in the cliffs, 

 upper head, 5 feet thick, caps the cliff. The material is similar 

 to the lower head, but is, perhaps, less compacted. It forms a flat 

 cone spread out on the terrace of drifts, and its apex points up a 

 small valley cut into the hillside above the terrace. The tiny 

 stream which flows down the valley has not succeeded in cutting 

 through the cone. 



Near the eastern end of the line of cliffs an irregular mass of 

 gravel, composed almost entirely of subangular and rounded 

 pebbles of Old Red Sandstone and Carboniferous rocks, overlies 

 the marl. 



Beyond this the cliffs are interrupted by the valley which 

 enters the bay from the north. On the other side of the valley, 

 below the Coastguard Station, the pre-glacial cliff is nearer the 

 present cliff, and the platform rises towards it. 



The coast east of Bally croneen Bay. — A section just east of the 

 Coastguard Station has been described on p. 256, and two well- 

 rolled pebbles of igneous rock found in the beach deposits 

 recorded on p. 261. 



The beach-gravel may be traced along the platform to the 

 eastward. At one point, about 6 inches of blown sand rests on 

 the gravel, and is overlain by head. The gravel also contains a 

 few large fallen blocks. 



In the small bay, 400 yards to the east of the Coastguard 

 Station, stratified gravel 5 feet thick rests on the platform, and is 

 overlaid by a thick deposit of head. The cliff is capped by reddish 

 clay with angular and rounded stones, probably boulder-clay. 

 The platform can be plainly followed into every bay and 

 round every headland, though the beach-gravel may not always 

 be present. It is about 10 feet above the modern shore-platform. 

 The head, when seen close to the pre-glacial cliff, often resembles 

 screes in structure. 



