February, 191 5. 



The Irish Natvralht. 



^7 



A LIST OF THE LAND AND FRESHWATER 

 MOLLUSCA OF THE DINGLE PROMONTORY. 



BY A. W. STELFOX, IM.KM.A. 



The present paper deals with that portion of the Dingle 

 peninsula contained in the old Barony of Corkaguiny, 

 which, according to Praeger's division of Ireland, is included 

 in the vice-county of South Kerr^^ It includes the Great 

 Blasket and the attendant islands, " the nearest parish to 

 America," situated off the extreme western point ; also 

 the Seven Hogs or Magharees at the entrance to Tralee 

 Bay. 



Much of the peninsula lies at a height exceeding 2,000 feet, 

 Brandon Mountain attaining the greatest elevation in 3,127 

 feet. Everywhere deep valleys, coombs, or rock -basins lie 

 between the mountains, but the coombs are particularly in 

 evidence to the north of the main watershed. Cliffs with 

 rich, though low-growing, vegetation are frequent, especially 

 around Brandon Mountain and Connor Hill. Slates of 

 Silurian and Old Red Sandstone age form the greater part 

 of the district, but the presence of Glacial drift containing 

 limestone along the shore of Tralee Bay mitigates to 

 some extent the unfavourable nature of the slates and 

 conglomerates. The great areas of sand dunes round the 

 coast, which include in their composition a large percentage 

 of calcareous material, likewise have a stimulating effect on 

 the molluscan fauna. Were it not for these sandy areas 

 the list of species would be considerably diminished, not 

 only in the case of the land shells, but also in that of the 

 freshwater species. The chief habitat for the latter is the 

 strip of marsh -land which lies behind the fringe of dunes 

 for several miles east and west of Castlegregory. The 

 Magharees and the peninsula stretching north from Castle- 

 gregory are formed of Carboniferous limestone, but no 

 part of this limestone area have I been able to work. 



Compared with some other districts in which I have col- 

 lected, such as West Mayo, the Dingle promontory cannot be 

 said to be heavily peat -covered ; yet in the valleys and on 

 the northern slopes of the mountains much of the ground 



