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THE LAND AND FRESHWATER SHELLS 

 OF TENBY, SOUTH WALES. 



By ARTHUR G. STUBBS. 



(Read before the Society, February 14th, 1900). 



Tenby has long been noted for Marine Mollusca, also for the very 

 local snail H. piscina-, but I believe that no serious attempt has 

 hitherto been made to form a complete list of the other land and 

 freshwater species that are to be found in the district. I have 

 confined this list to the immediate neighbourhood of Tenby (roughly 

 a radius of three miles from the centre of the town) with the exception 

 of a few references to Pendine, which has sandhills and marshes very 

 similar to those at Tenby; and to the neighbouring village of Manorbier. 



The most noteworthy absentees from the land forms are the species 

 of Vertigo, but these minute shells are easily overlooked and possibly 

 one or two species do occur. Of the freshwater forms Valvata cristata 

 is the only representative of the order Operculata that is found in the 

 district; this would in some measure be accounted for by the absence 

 of rivers, canals, or large bodies of water; though the two Bythiriics 

 and V. piscinalis might have found conditions suited to them in the 

 Ritec stream, or some of the ditches in the marshes. The Unionidse 

 are only represented by Anodonta anatina var. complanata; however, 

 the reason given above in the case of the Operculata would apply 

 equally well to this group. 



I am indebted to Messrs. L. E. Adams and W. Denison Roebuck 

 for their kindness in authenticating several of the slugs for me. 



Brackets denote species given on the authority of others, but which 

 have not as yet been confirmed personally. The nomenclature is 

 that of the Conch ological Society's List. 



Arion ater. — Common, the type form being the one usually met 

 with. 



Var. brunnea. — Specimens from Holloway Quarry, and Hoyle's 

 Mouth, not common. 



Var. ? — An interesting banded form of this species is to 



be taken down by the Harbour, from under old logs. In young 

 specimens the bands are very distinct, but as the animal approaches 

 maturity, the bands become rather fainter and the whole slug much 

 darker. There is a dark band down the centre of the back, and one 

 down each side, the intervening spaces being pale grey or sometimes 

 pale yellow. The cross-striation on the foot-fringe is of the same 

 shade as the dark bands, but is faint on very young specimens. 



