90 



Proceedings of the Royal Irish Academy. 



Hygromia rufescens (Pennant). 



Helix rufescens, Thompson, Cat. L. & 

 F. W. MoU. of Ireland, p. 14, 1840. 



WD ED LD AN 

 FE TY AR DO 

 WMSL LE MO 



EM RO CV LH 

 WC NG LF WH ME 

 SG KG KD DU 

 CL NT QG GW Wl 

 NK LK ST KK WX 

 SK MG EG WA 

 WG 



Thougli found in all divisions and on 

 the Aran Islands, this must he looked 

 npon as distinctly an eastern and central 

 species, and one -svhich has all the 

 appearance of heing among the latest 

 arrivals in this country. In the north 

 and vest it is seldom native, as far as 

 one can judge, and usually appears 

 naturalized. It is one of our few shells 

 ■which is clearly extending the range of 

 its distrihution at the present day ; and 

 it is constantly turning up in fi'esh 

 localities, especially gardens, where it 

 is easily introduced with plants, and 

 seldom fails to establish itself.' Being 

 to a certain extent a " iiedgerow " 

 species, the present cultivated condition 

 of the country is adrairahly suited to its 

 requirements ; and it occurs in great 

 quantities iu such habitats in the 

 central and eastern counties. It varies 

 greatly, from white to a rich dark-brown 

 in colour, and in shape from almost flat 

 to a high-spired and conical shell. 



' Its liking for Arabis albida has often been 

 noted bv nie, and few gardens where this plant 

 grows do not also shelter S. riifeseens. 



Sometimes it is keeled obtusely ; but 

 more often this is absent when the shell 

 is full-grown. Probably at least three 

 continental "species" are included ia 

 our Irish SJygromia rufescens. 



Acanthinula aculeata (MiiUer). 



Helix aculeata, Thompson, Cat. L. & 

 P. "W. lIoU. of Ireland, p. 11, 1840. 



WD ED LD AN 

 FE TY AR DO 

 WMSL LE MO 



EM RO CV LH 



WGNC LF WHME 

 SG KG KD DU 



GL NT QG GW Wl 

 NK LK ST KK WX 

 SK MG EG WA 



WC 



Generally distributed, but never met 

 with ia such quantities as the next 

 species.. From the number of dead shells 

 found in our sand-dunes this would 

 appear to have formerly been a more 

 abundant species. "WTiite specimens 

 frequently occur, and spineless ones have 

 been recorded from several localities. 

 This latter form, the var. suhlaevis of 

 "^esterlund, is never common ; and it 

 has, so far as my experience goes, only 

 been taken occasionally on the stony 

 margins of lakes, and never in company 

 with the type. 



Acanthinula aculeata is frequent but 

 by no means common on the western 

 islands. Juvenile specimens of the 

 western form of Pupa cylindracea closely 

 resemble A. aculeata var. svMaevis, but 

 the latter can be distinguished by its 

 deeper suture. 



