670 MR. F. R. COWPER REED ON THE [Nov. I9OO, 



rocks, but its height from the base of the steep cliffs renders it 

 inaccessible. 



That all these felsitic rocks are earlier than the deposition of the 

 red sandstones and conglomerates, is the only fact with regard to 

 their age which can be asserted. All have suffered disturbance 

 prior to the formation of these later rocks. 



Killelton Cove. — The greenish felsite of the cliffs seems to 

 consist of a series of superposed sheets dipping eastward at about 

 30° when we trace them into the adjoining Killelton Cove, where 

 also the coarse greenish ash reappears, though separated from the 

 felsite by a fault. A dyke of dark felsite is here observed cutting 

 the greenish felsite and ash, together with other intrusions ; and in 

 the western Killelton Cove (part of which is called Lady's Cove) 

 the green felsite of the cliffs is found in contact with banded black 

 slates. Several dykes of greyish felsite pierce these slates, and are 

 more or less crushed with them. In one spot a mass of coarse 

 agglomerate, containing fragments of the slates, may represent a 

 volcanic pipe. 



Ballyvooney Cove. — Until we reach Bally vooney Cove no 

 other exposures of felsitic rocks occur, the cliffs being composed of 

 black and grey slates, but at this locality a coarse quartz-felsite of 

 later date pierces them, and encloses portions of both the slates and 

 the grey felsites which here reappear. 



Stradbally. — The huge boss of so-called greenish felsite extend- 

 ing along the coast for fully h mile south-west of Stradbally village 

 has burst through the slates, but appears, from slight variations in 

 its character, to be of composite origin. It is the westernmost of all 

 the felsitic and other acid intrusions along the coast, but its age and 

 relation to them is uncertain, and cannot be directly determined. 



b. Necks of Non-Volcanic Materials. 



In addition to the pipes associated with the felsitic and basic 

 mcks and rilled with fragments of similar materials, there occur 

 some which only contain a breccia of the surrounding rocks and are 

 not connected directly with any of the neighbouring lavas or volcanic 

 ashes. Such is one immediately north of Eaheen Bridge (near 

 Passage), where on the foreshore, about 150 yards north of the 

 stream, a small mound about 3 feet high and of somewhat irregular 

 outline, measuring 6 by 4j feet along its principal diameters, repre- 

 sents an old vent which has been drilled through the surrounding 

 mudstones. The pipe is filled with angular fragments of these 

 beds, and with pieces of black slate and fine-grained sandstone 

 embedded in a greyish paste of slate-dust. No igneous rocks or 

 ashes are observable in connexion with it, and its date is con- 

 jectural. In appearance it reminds one of some of the Permian 



