230
J. A. KITCHING AND F. J. EBLINO
Rapids, penetrating as far as the south-east corner of the South Basin.
It occupies the lowest fucoid zone and is covered by the sea for most
of the time. Clava squamata (Fig. 38) was found in 1955 only in or near
the Rapids (though small quantities were found elsewhere in 1958), even
though its substrate Ascophyllum is widely distributed.
3. Species Preferring Stations Remote from Open Sea
The intertidal fucoid algae, Pelvetia canuliculata, Fucus vesicubsus,
F . spiralis and Ascophyllum nodosum (Fig. 39), are common around
the shores of the lough and extend southwards as far as Bullock Narrows, but are absent from exposed seaward stations. It might be supposed that these fucoids are unable to endure powerful water movements, though it has been demonstrated a t Port Erin that removal of
Patella may lead a growth of fucoids on a shore where they wese previously very scarce (Jones, 1948; Southward, 1956). P. vulgata and
P. aspera are both very abundant intertidally at Carrigathorna and on
the south shore of Bullock Island; both species are much less abundant
within the lough, and P. aspera is entirely sublittoral.
Polysiphonia lanosa, Dynamena pumila, Dymmene bidentata, Flustrella hispida and Littorina littoralis (Fig. 40) are associated with
Ascophyllum and are found a t nearly all the stations where Ascophyllum
occurs; only Clava, as already mentioned, is more limited in distribution than its normal substrate. Gibbula umbilicalis and Hydrobia ulvae
are likewise found everywhere in the area except on the exposed coast.
Littorina littorea (Fig. 41), however, present in the lough and Rapids,
does not extend farther south than Southern’s Bay.
4. Species Found in All Parts of the Area
Relatively few intertidal forms were of general distribution. Ulva
Zuctucu occurred nearly everywhere, including South Bullock, though
not Carrigathorna. Littorina saxatilis was found at all thirty-three stations, and the barnacles Chthamalus stellatus and Belanus balanoides
were widely distributed. The distribution of Patella spp. has already
been mentioned and will be considered in detail in a separate section.
Mytilus edulis is common a t Carrigathorna, but occurs spasmodically
in Lough Ine, being abundant in the Goleen and on the north-east shore;
the evidence that its distribution is limited by predators will be discussed later.
c. THE SUBLITTORAL FRINGE
Two large brown algae are characteristic of the subIittoraI fringe -
namely Alaria esculenta and Himanthalia elongata. Alaria (Fig. 42) is
almost confined to the full sea stations and appears to require exposure
J. A. KITCHING AND F. J. EBLINO
Rapids, penetrating as far as the south-east corner of the South Basin.
It occupies the lowest fucoid zone and is covered by the sea for most
of the time. Clava squamata (Fig. 38) was found in 1955 only in or near
the Rapids (though small quantities were found elsewhere in 1958), even
though its substrate Ascophyllum is widely distributed.
3. Species Preferring Stations Remote from Open Sea
The intertidal fucoid algae, Pelvetia canuliculata, Fucus vesicubsus,
F . spiralis and Ascophyllum nodosum (Fig. 39), are common around
the shores of the lough and extend southwards as far as Bullock Narrows, but are absent from exposed seaward stations. It might be supposed that these fucoids are unable to endure powerful water movements, though it has been demonstrated a t Port Erin that removal of
Patella may lead a growth of fucoids on a shore where they wese previously very scarce (Jones, 1948; Southward, 1956). P. vulgata and
P. aspera are both very abundant intertidally at Carrigathorna and on
the south shore of Bullock Island; both species are much less abundant
within the lough, and P. aspera is entirely sublittoral.
Polysiphonia lanosa, Dynamena pumila, Dymmene bidentata, Flustrella hispida and Littorina littoralis (Fig. 40) are associated with
Ascophyllum and are found a t nearly all the stations where Ascophyllum
occurs; only Clava, as already mentioned, is more limited in distribution than its normal substrate. Gibbula umbilicalis and Hydrobia ulvae
are likewise found everywhere in the area except on the exposed coast.
Littorina littorea (Fig. 41), however, present in the lough and Rapids,
does not extend farther south than Southern’s Bay.
4. Species Found in All Parts of the Area
Relatively few intertidal forms were of general distribution. Ulva
Zuctucu occurred nearly everywhere, including South Bullock, though
not Carrigathorna. Littorina saxatilis was found at all thirty-three stations, and the barnacles Chthamalus stellatus and Belanus balanoides
were widely distributed. The distribution of Patella spp. has already
been mentioned and will be considered in detail in a separate section.
Mytilus edulis is common a t Carrigathorna, but occurs spasmodically
in Lough Ine, being abundant in the Goleen and on the north-east shore;
the evidence that its distribution is limited by predators will be discussed later.
c. THE SUBLITTORAL FRINGE
Two large brown algae are characteristic of the subIittoraI fringe -
namely Alaria esculenta and Himanthalia elongata. Alaria (Fig. 42) is
almost confined to the full sea stations and appears to require exposure