Wright and Muff — Pre-glacial Raised Beach. 267 



Toughal Bay. 



Astarte sulcata, Da Costa. 

 Maetra solida, Sow. 

 Tapes decussatus, Linn. 

 Mytilus, sp. 

 Tellina balthica, Linn. 

 Turritella terebra, Linn. 



The marl also contains subangular and rounded stones, some of 

 which are striated. They are scattered sparingly throughout it, 

 but are occasionally seen to be more abundant in its upper 

 portion. In this connexion it may be noted that a striated 

 surface has not yet been found beneath the marl along the 

 south coast. The stones are of various sizes ; and, in addition to 

 local rocks, include a number of distant origin, amongst which 

 chalk-flints are the most abundant. A series of fine-grained 

 porphyritic rocks, which seem to include quartz-porphyry, felsite, 

 andesite, porphyrite, and dolerite, form the largest class of igneous 

 rock. Some of them are identical with — and others closely 

 approach — specimens of the igneous rocks associated with the 

 Silurian sediments of Waterford, Wexford, and Wicklow. Some 

 gneisses and altered basic igneous rocks (epidiorites) are similar 

 to rocks cropping out on the shore between Greenore Point and 

 Carnsore, County Wexford. A white granite, with dark quartzes 

 and drusy cavities, is exactly like the Mourne Mountain granite; 

 and one or two basic rocks correspond with some occurring on 

 Slieve Foy, County Louth. 



List of Bouldees eeom the Maeey Bouldee-Clay. 



Battycroneen Bay. 



Hard chalk. — Antrim, or possibly bed of Irish Sea. 



Glaneonitic chalk. — Antrim, or possibly bed of Irish Sea. 



Grey and black flints. — Antrim, or possibly bed of Irish 

 Sea. 



Hornblende micro-granite. — Similar granites occur at 

 Crosspatrick, five miles east of Shillelagh; Croghan 

 Kinshela ; and on Great Saltee Island. 



White granite, with druses. — Mourne Mountains. 



SCIENT. PROC. R.D.S., VOL. X., PART II. Y 



