106 



Proceedings of the Royal Irish Academy. 



mucli less rugged than those whioh 

 have lived in drier situations. On 

 Cruit Island, in West Donegal, this 

 shell lives on the short grass and under 

 cow-dung on the 'western cliff -slopes, 

 within easy reach of spray during 

 vresterly gales, and must depend entirely 

 for its supply of water on dew and rain. 

 Shells living in such a locality must 

 vary greatly from year to year according 

 to the amount of rain that falls during 

 the season of their growth ; and it is to 

 he regretted that up to the present we 

 have no data to tell us the amount or 

 the direction of this variation. 



Succinea oblonga Dr8,parnaud. 

 Plate VII, figs. 48-50. 



WD ED LD AN 



FE TY AE DO 

 WMSL LE MO 



EM EO CV LH 

 WG NG LF WH ME 



SG KG KD DU 



CL NT QC cw wi 



NK LK ST KK WX 



SK MC EC WA 

 WC 



Habitats for this very local species 

 are known in all four provinces ; and in 

 some of these it may he collected in 

 large numbers. Its distribution, how- 

 ever, as at present known, is exceed- 

 ingly discontinuous ; but the majority 

 of its stations lie in the southern or 

 western counties. It shows no prefer- 

 ence for any particular kind of habitat, 

 nor is it apparently affected by the 

 prevailing petrological conditions, as 

 scarcely any two of these are in any 

 way similar. Specimens from several 



localities, but especially those from 

 the Dooaghtry sand-dunes in West 

 Mayo (fig. 49), are very similar to 

 Moquin Tandon's conception of Sucoinea 

 arenaria Bouch-Chant., i.e. small, deep- 

 red in colour, and with a deep suture, 

 while the shells from the shore of 

 Lough Neagh in Antrim are greenish 

 in colour with large body whorl and 

 less strongly marked suture (fig. 50). 

 The larger and more elongated ex- 

 amples found along the southern shore 

 of Lough Erne, at Carrickreagh, in 

 Fermanagh (fig. 48), have been re- 

 ferred by the late Prof. Boettger to 

 the var. agonostoma Kiister. Mr. Phillips 

 has taken this species on Inishmore, in 

 the Aran Islands, this being the only 

 record for the species other than from 

 the mainland. 



AURICULIDAE. 

 Carychium minimum Miiller. 



WD ED LD AN 

 FE TY AR DO 

 WMSL LE MO 



EM RO CV LH 

 WG NG LF WH ME 

 SG KC KD DU 

 CL NT QC CW Wi 

 NK LK ST KK WX 

 SK MC EC WA 

 WC 



Is almost universally distributed 

 throughout the mainland, and generally 

 found on the western and other islands ; 

 but on a recent visit to Tory Island I 

 was unable to find it. Varies greatly 

 in size and in the proportion of width 

 to height, specimens from some districts 



