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A LARGE RACE OF CEPAEA NEMORALIS L (AND OTHER MOLLUSCA) AT HIGH ALTITUDES IN THE GALTEE MOUNTAINS, CO. TIPPERARY SOUTH.

By A. W. STELFOX.

The presence of nemoralis at high levels in the mountains of Co. Sligo is usually put down to the fact that these mountains are formed of Carboniferous Limestone. The Galtees, on the other hand, are composed of rocks of Old Red Sandstone and Silurian ages. It was therefore a surprise to me, on visiting the Galtees for the first time, in September, 1943, to find on the Old Red Sandstone cliffs west of Muskry Lough a large race of nemoralis, very like that which occurs on some of the Sligo mountains. In May-June, 1944, a few similar shells were also taken on the cliffs above Lough Diheen-also Old Red Sandstone. These Galtee specimens were taken at an altitude of between 1,800 and 2,000 feet, and nemoralis no doubt occurs higher than this, as the cliffs rise almost unbroken from the tarns to a height of about 2,500 ft. I was not looking for mollusca on either of my visits to the Galtees, and I regret that time did not permit me to make a thorough search for them. I can therefore assure Dr. Comfort, or anyone with an equal store of energy, that the Galtees offer quite a likely field for research to anyone interested in these large nemoralis. 
Many old, dead, and broken nemoralis were seen at the foot of the cliffs above Muskry L., and most of the few living ones seen showed repairs from injuries received from being blown off the cliffs or knocked down by sheep, which scramble all over them like goats. Those taken above L. Diheen were on a shelf not invaded by sheep, had more peace and shelter, and were larger and undamaged. Specimens from Muskry L. measure about 23 mm. in width by 17 mm. in height; those from L. Diheen 23 to 25 X 20 mm. 
In colour most are, like those from Sligo, reddish and unbanded, and many have white lips. One red specimen with band formula 00300 was taken in 1944, and some fragments of banded shells also seen. 
Other mollusca undoubtedly occur at about 2,000 ft above Muskry L., and a hasty search yielded Columella edentula, Goniodiscus rotundatus, Retinella nitidula, and Ancylastrum fluviatile. 
The last was abundant on the wet surface of the cliffs, where it was living an almost terrestrial life, but these cliffs face east and north, and only get the sun very early in the morning during the height of summer ; moreover, I fancy they are very seldom actually dry. Curiously enough I failed to find Ancylastrum in Muskry L. itself, though dead shells were found in the delta of a small rivulet coming down from the cliffs, but it occured in another of the tarns, L. Borheen, and in the outlet of L. Curra, in both cases at about 1,600 feet. The only mollusca seen on the main ridge, which in Galtymore reaches an altitude of 3,018 feet, were Arion ater, v. aterrima, and A. subfuscus. Many of the former slug were seen eviscerated, presumably either by ravens, rooks, or hoodie crows, but I have no proof of this.