290 



ON IIYGROMIA EUFESCENS, AUCT./ IN IKELAND. 



By A. W. SxELFox. 



Bead 10th January, 1913. 



During the lust few years, at least some couchologists in this country 

 have awakened to the fact that the inclusion of ' j^arden records ' in 

 tables ostensibly intended to show the geographical distribution of 

 a species is liable to obscure rather than demonstrate its natural 

 range. ^ 



For many years, however, it has been the custom for certain 

 English couchologists to ' fill up gaps ' in the census by requesting 

 gardeners of estates to forward molluscs for identification. Thus the 

 accumulation of garden records has reached no mean proportions, and 

 the apparent natui-al range of some of our Irish species has been 

 affected thereby. 



Among these, Htjgromia rufescens, auct., may be taken as an 

 example. This is a ' Central European ' species, with its Britannic 

 headquarters in the south-east of Enghmd, and thus it belongs to 

 that element of our fauna which one might not expect to find in 

 Ireland. 



After some years investigation, I have grave doubts whether 

 //. rnfescens can be considered a native^ of Ireland, although it has 

 been ' found ' in all the forty divisions of the island, and I am more 

 and more inclined to agree with the opinion of my friend Mr. Welch 

 that " it probably came to Ireland with the Englisli ". At the time 

 of the publication of the " Irish List 'V i" 1911, 1 had not studied the 

 problem sufficiently to give a decided opinion ; but since that date 

 I have accumulated much evidence, all of which tends to throw doubt 

 upon the standing of tliis species in Ireland. 



This evidence may be put in a tabulated form as follows : — 



1. I know of no records for H. rufescens from uncultivated or 

 undisturbed ground. It appears to be purely a 'hedgerow' and 

 ' garden ' inhabitant in Ireland, whereas in the »South of England it 

 occurs in woodlands on the Downs, associated with species unknown 

 elsewhere in Britain, and is as unquestionably native as a species can be. 



2. Records come mainly from the environs of towns and villages, 

 and more especially from tliose wlu're English settlers are known to 

 have dwelt. In fact, its headquarters in Ireland lie witliin the 

 boundaries of the Pale.^ 



Mr. E. A. Smith has shown that this is not the species described and figured 

 by rennant, Ann. Mag. Nat. Hist., 1913, vol. xi, p. 263. 



See L. E. Adams, Journ. Conch., vol. xiii, pp. 211-14, 1911. 



For a definition of a 'native' see S. T. Dunn, Alien Flora of Britain, 

 pp. 9-10. 



Proc. Eoy. Irish Acad., vol. xxix, sect. B, pt. iii, 1911. 



Nearly synonymous with the province of Leinster, but not so extended 

 in area. 



