iS97-] Standkn. — Land Molhisca of Bally castle. 7 



H. aspersa, MUller. — The constancy of marking exhibited by this 

 species throughout Ireland has often been noted, and the vast number 

 of specimens observed in our district were, generally, no exception to the 

 rule. At Whitepark nothing approaching any particular "variety " was 

 noticed amongst the thousands we saw. At Murlough a little less uni- 

 formity occurred, and one good typical var. nndidata was taken, along 

 with a form approaching grisea, on rocks near the footpath. A very 

 dark and almost unicolorous specimen was found in Miss O'Connor's 

 greenhouse. Otherwise the shells everywhere looked much alike, and 

 their good and unweathered condition was remarkable, considering the 

 exposed places in which many were living. The Chalk cliffs at White- 

 park presented a wonderful spectacle. In many parts they are fitted 

 with regularly-shaped holes of different sizes, and in every hole rested 

 a H. aspersa, the dark shell showing up conspicuously against the white 

 background. On one little bluff, about 4 yards bj'- 2, we counted over 200 

 specimens — and this did not include those far down in the crevices. 



The first impression was that the shells are resting in natural cavities 

 caused by the weathering out of flint nodules or fossils, but a more 

 critical examination shows all the holes to be fairly symmetrical : they are 

 not anything like as irregular as flint-cavities, and, besides, there are no 

 flints there. So far as I can ascertain there are no holes like these else- 

 where in the county. Almost all the holes run up vertically, a few nearly 

 so, none down, and most of them are underneath the little ledges left in 

 the face of the cliff by weathering. Dr. Scharff alludes to this habit of 

 H. aspersa in Irish Naturalist, vol. I, p. 118, and quotes M. Bouchard- 

 Chantereaux's experiments, which point to the presence of an acid 

 secretion in the animals which might have an influence in softening the 

 hard chalk, and thus enabling the snail with its rasp-like tongue to 

 remove the material. This is very probable, but from my own observations 

 on some aspersas in captivity ('), which ate enormous quantities of chalk — 

 so much so, that the pot in which they were confined was strewed with 

 their excreta in the form of white pellets, covering the snail to a consider- 

 able depth — I should say that the gradual gnawing away of the soft 

 weathered chalk of the Whitepark cliffs by successive generations of 

 aspersas would very well account for the remarkable holes tenanted by the 

 shells there. The diameter of many holes is larger inside, and there is a 

 general look of freshness immediately underneath the animals, which 

 seems to point very conclusively to the holes being their own work. 



Cochlicopa !ubrlca, Miiller.— In the Whitepark "pockets" 

 thousands occur — living and dead together — and it is fairly plentiful 

 everywhere, together with its varieties ovata and lubricoides. Var. hyalina 

 occurred at Murlough and Glenshesk, Rathlin Island, and Ballintoy, 

 1889 (Welch). 



Pupa angelica, Fdr. — A few very dark-coloured specimens at Mur- 

 lough ; some nice examples of var. pallida at Glenshesk, and a few dead 

 in "pockets," Whitepark. 



' fotirn. of Conch. ^ vol. vii., p. T^^i- 



