34 



The hish Nairn ai is L 



February, 



of Coumaknock, to 2,300 feet. This is the only Pisidium mentioned 

 by Mr. Tomlin in his list. 



Pisidium personatum Malm. — Occurred in what is probably the highest 

 possible habitat for a freshwater shell in Ireland : St. Brendan's well on 

 the summit of Brandon Mountain I Also taken in the tarns below this, 

 in Lough Anscaul, and in the marshes at Stradbally. 



P. milium Held. — -Lough Anscaul ; in the marshes at Stradbally ; and 

 in the Coumaknock tarns, to 1,675 feet. 



P. Lilljeborgi Clessin. — Common in Lough Tooreenmartin, 1,200 feet ; 

 Coumenare Lakes, 1,100-1,350 feet ; Lough Doon, 1,050 feet ; Lough 

 Nalackan in Coumaknock, Brandon Mountain, at 1,150 feet ; and 

 also in Lough Gill, which is but fourteen feet above sea-level. 



All the above records for the Pisidia are on the authority 

 of Mr. B. B. Woodward, and I have to thank him once 

 more for his great kindness in naming specimens sent to 

 him. The record for P. pusillum from the cliffs near Brandon 

 Head, and that for P. personatum from St. Brendan's well, 

 show how comparatively easy it must be for these species 

 to cross the barriers which divide one river basin from 

 another. The construction of the well above mentioned 

 precludes, I think, all possibility of the specimens having 

 been carried by birds. When returning my specimens 

 Mr. Woodward remarked on the fragility of the shells from 

 the tarns in Coumaknock, on Brandon Mountain. My 

 remarks under Ancylus fLuviatilis are referable to these 

 shells also. 



Several of the above species, although generaUy dis- 

 tributed throughout the promontory, are much less plentiful 

 than we find them in the north of Ireland. This is particu- 

 larly noticeable in the cases of Vitrina pellucida and 

 Hygromia hispida, as well as in those of Agriolimax laevis, 

 Arion subfuscus, and A. circuniscriptus. The presence of 

 so many freshwater species, belonging to the group which 

 has its headquarters, in Ireland, in the central plain, is of 

 interest. Their range in the district is a limited one, however, 

 and none but Physa fontinalis has been found beyond the 

 long tract of marsh -land which lies behind the dunes, from 

 Fermoyle to Castlegregor}^ Eastward of the latter place 

 along the southern shore of Tralee Bay there is much low- 

 lying marshy country/, and between Tralee and the basin 

 of the Shannon there is also no great barrier to dispersal. 

 Hence, I think, we may trace their origin. As stated above, 



