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SOME NOTES ON THE NEW BRITISH LAND SHELL, 

 HELICELLA HERIPENSIS Mabille. 



By Rev. C. E. Y. KENDALL 



(Read before the Society, April loth, 1Q12). 



In Vol. X., part i, of the " Proceedings of the Malacological Society" 

 published in March, 191 2, Mr. A. W. Stelfox, of Belfast, contributes 

 an interesting and important paper, announcing the discovery in Great 

 Britain of a new species of land shell, Helicella heripensis Mabille, 

 hitherto only known on the continent. His paper contains a detailed 

 comparison of this species with its congener Helicella caperata Mon- 

 tagu, and a list of localities in twenty of the British vice-counties 

 where it has been found. Mr. Stelfox holds that it is a " good " 

 spiecies and in this opinion he will undoubtedly be supported by those 

 who have collected the shell, as in outward appearance it is far more 

 strikingly dissimilar to Helicella caperata than some other already well 

 recognized species of the Candidula group. I have written these 

 notes with some dififidence, but trust that my observations made 

 during the past two years may be of some interest to some of my 

 fellow conchologists who have not yet had the opportunity of collecting 

 this species. 



§ I. The shell. 



For a detailed description I will refer readers of these notes to the 

 paper by Mr. Stelfox, who has there set out the points of resemblance 

 and difference in a very clear and concise manner. I would only 

 point out that the most striking difference between H. heripensis and 

 H. caperata lies in the umbilicus, which in the former shell is wide, 

 deep and open, exposing the coiling of the whorls, which are wound 

 excentrically round the axis. In fact in general character Helicella 

 heripensis bears the same relationship to H. caperata that Vallonia 

 excentrica does to V. costata. Variation in colour exists to a certain 

 degree, but does not seem so great as in H. -caperata. Mr. Stelfox 

 describes the shell as " usually of a creamy-brown colour, but often 

 pale cream, with radiating markings." I have specimens which both 

 descriptions fit exactly, and also have taken in this district (North 

 Northants) a number of specimens of a rich fulvous colour, which 

 could suitably be described as 



var. lutescens. — Shell, a wet sand colour without markings. 



I have also some beautiful shells taken near Brighton of a pure 

 white colour with dark apex, which on the analogy of H. virgata one 

 would naturally describe as 



