92 



Proceedings of the Royal Irish AcaJemy. 



and BelmuUet peninsulas iu South 

 Kerry and "West Mayo respectively, 



WD ED LD AN 



FETY AK DO 

 WMSL LE MO 

 EM EO CV LH 



WG NG LF WHME 



SG KG KD DU 

 CL NT QC CW Wl 



NK LK ST KK wx 

 SK MC EC WA 



wc 



it has never been reported as living 

 on any of the western islands. It is 

 also common on many of the diy 

 coastal dunes of north Ulster. We 

 may expect that in the future, if it 

 has not ali-eady heen done, this species 

 will also be divided into two, as some 

 specimens with a more exeentric appear- 

 ance are frequently met with. In many 

 localities this and V. pulcliella are found 

 associated ; but, as a general rule, they 

 are found in separate colonies. 



Arianta arbustorum (Linne). 



Helix arhustormn, Thompson, Cat. L. & 

 F. W. Moll, of Ireland, p. 9, 1840. 



WD £D LD AN 



FE TY AR DO 



WMSL LE ^J^o 



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 



From its wide range throughout Great 

 Britain, it is surprising how local this 

 shell is in Ireland ; and its distribution 

 should prove of great interest to students 

 of the geographical distribution of 

 animals and plants. It would appear 

 that tliis species is one of a group of 

 migrants which entered Iieland from the 

 north. In the glens of Antrim Arianta 

 arbustorum is closely associated with the 

 other northern immigrants, which are 

 mostly plants ; but in no way does it 

 depend on any of these for food, not 

 actually living in contact witli them, 

 but in their neighbourhood. Its food- 

 plants are apparently those which 

 have a general distribution in this 

 country, such as the Common Nettle 

 {Urtica dioica). From Henbane in north 

 Antrim to the Belfast hills in the 

 same county Arianta arbustorum is found 

 locally in many of the glens ; and 

 in the mountain glens of Sligo and 

 Leitrim it again appears in fair abun- 

 dance. Between these two areas the 

 shell is extremely local and rare, but 

 the isolated habitats, such as that at 

 Coagh in Derry, help us to trace its 

 former range ; and it is more than 

 probable that many such habitats exist 

 in the more mountainous districts of 

 Derry, Tyrone, Fermanagh, and Cavan, 

 which up to the present are quite a 

 terra incognita to conchologists. The 

 records for Armagh and Westmeath 

 apparently mark the limits of its range 

 in those directions ; those from Dublin, 

 Limerick, and North Kerry being seem- 

 ingly erroneous. Thompson mentions 

 that the species prevails throughout tlie 

 county of Antrim, " as it likewise does 

 in Down, but more sparingly." There 

 are, however, no specimens of this shell 



