292 Scientific Proceedings, Royal Dublin Society. 



by a large cone of head, the apex of which points up a valley. 

 The stream which occupies the valley has cut a narrow but deep 

 channel through the head. The cone rests on the rock-platform, 

 and has been eroded by the sea, so that it is now cut off by cliffs 

 from 12 to 40 feet high. It is composed of angular debris of red 

 sandstone with reddish loamy layers, which dip seawards at low 

 angles. 



Ballyandreen. — On the west side of the cove at Ballyandreen, 

 the platform was seen overlain by head, and a thin deposit of 

 boulder-clay, containing flints and small shell-fragments. On the 

 east side there are vertical rock-cliffs, capped by a variable thickness 

 of head ; but a stack, standing a short distance from the cliff, and 

 planed off from 5 to 6 feet above high- water mark, is surmounted 

 by a thick deposit of head, and points to the local destruction of 

 the platform and its overlying deposits of drift. 



Batty cottin. — On the southern shore of Ballycottin Bay the 

 beach-deposits are fairly well developed, being in some places 

 overlain by boulder-clay of the Cork type, and in others by the 

 shelly marl of the eastern ice. The following sections can be seen 

 on the shore, north-east of the chapel, close to the end of a lane: — 



Feet. 

 Head, yellow and clayey, . . 10 



Beach-gravel and sand, . . 5 



Eock-platform. 



There is a pasty band, 1 foot thick, at the bottom of the head. 



The rock-platform is 5 to 7 feet above ordinary high-water mark. 



About 60 yards east of this, we have — 



Feet. 



Boulder-clay, . . . . . . 8-12 



Head, .. .. .. .. 12-8 



Beach-gravel and sand, . . . . 2-3 



Eock-platform. 

 The boulder- clay is of the Cork type, but contains an occasional 

 flint. The rock-platform is 5 feet above ordinary high-water 



mark. Below Bayview Hotel : — 



Feet. 



Marly boulder- clay, . . . . . 5 



Head, . . . . . . . . 18 



Gravel and rounded boulders . . . . traces. 



Rock-platform. 



