TRANSACTIONS 



OF THE 



lladturai ptstora Scrmtj) of (ilasplu- 



Notes on the Marine Mollusca of Port Stewart, 

 North Ireland 



(Especially in their relationship with the Clyde Fauna). 

 By Rev. G. A. Frank Knight, M.A. 



[Read September 26th, 1899. 



The northern coast-line of Ireland presents a striking diversity 

 of scenery and rock formation. As one sails round the Mull of 

 Cantire, passes the great island of Rathlin, and skirts the main- 

 land onward through the Skerries to Portrush, views are obtained 

 of some of the finest examples of cliff structure in the world. 

 The Giant's Causeway, which faces the gales of the North 

 Atlantic, is justly celebrated for its marvellous exhibition of the 

 form adopted by basalt in the act of cooling from a molten con- 

 dition. But the picturesqueness of its columnar structure is 

 greatly enhanced by the frowning crags which encircle and rise 

 far above it, and the sight of the great Atlantic billows dashing 

 themselves against the bases of these precipices is a thing to be 

 indeed remembered. With several breaks in the basaltic forma- 

 tion, as, for example, at Dunluce Castle, there is a more or less 

 continuous wall of rock from Ballycastle in the east to Port- 

 Stewart in the west. Sanely bays are occasionally found, wedged 

 in between the volcanic masses, and these intervals in the ram- 

 part have been seized on as sites for villages and towns. Port- 

 rush is built on a rocky promontory which is flanked by two 

 sandy bays, while Port-Stewart, five miles further to the west, 

 skirts a sapady enclosure, which is guarded by two rocky head- 

 lands. 



But a mile beyond Port-Stewart the scenery totally changes. 

 The precipitous crags disappear, and their place is taken by a 

 wide stretch of beautiful firm sand, skirted by great rolling sand 

 dunes, with bent. This is the character of the coast for several 

 miles. The same sandy scenery is continued across the River 



