62 
The Irish Naturalist, 
INIarch, 
THE IvAND AND FRESH-WATER MOIvIyUSCA 
OF NORTH-WEST DONEGAI.. 
I. BUNBEG, GWKEDORE, HOKN HkAD. AND GlKNVKAGH ArEAS. 
BY A. W. STe:i,FOX. 
[Plate 2.] 
The north-west corner of the large county of Donegal does not 
seem to have been hitherto explored by any conchologist, 
though limited areas have received fair attention. This was 
the main factor which influenced Dr. Chaster and myself in 
selecting the district for our holiday resort. This part of 
Donegal consists chiefly of granite, though at Horn Head 
smaller areas of quartzite and intrusive diorite occur. Peat 
bogs cover the greater portion of the underlying rocks, so 
that; except for a narrow strip round the coast and the lake 
shores, the ground does not favour moUuscan life. Large areas 
of blown sand occur, and these dunes are highly calcareous, 
being composed of finely comminuted shells, and seem to make 
up in that respect for the scarcity of limestone rocks These 
latter are represented only by small outcrops of crystalline 
limestone. The greater portion of the dunes is poor collecting 
ground, owing to the constant shifting of the sand, but the 
landward dunes, being turfed over, and lakes having formed 
in their hollows, provide excellent habitats for species not 
usually associated with sand-hill areas. Some of these lakes 
are of fairly large extent, as for instance Mullaghderg, four 
miles soitth-west of our headquarters at Middletown, Bunbeg. 
The shores of this lake contributed no less than forty species 
to our list— the largest number we obtained in any restricted 
locality. The mainland near Bunbeg was very disappoint- 
ing, while the peninsula of Carrickfin, though only separated 
by a narrow channel, proved fairly good collecting 'ground. 
This peninsula, and the district lying around Mullaghderg 
lyOUgh, would, w'e believe, well repay further investigation. 
None of the outlying islands were visited, but Inishcoole 
(Skull Island), close to Bunbeg, and Inisliinny, off the north 
of Carrickfin peninsula, were searched. Both these islands 
