319 



JAMINIA TRIPLICATA Studer, A NEW BRITISH 

 TERRESTRIAL MOLLUSC. 



By GEORGE W. CHASTER. 



(Read before the Society, March 14, 1906). 



In July, 1904, I spent a few days at the quaint, old-world village of 

 Brandon, in Suffolk, whose chief industry, flint working, has been 

 carried on uninterruptedly from prehistoric times. I was principally 

 occupied in collecting Coleoptera and it was by a mere chance that I 

 came across the mollusca which are the subject of this note. 



The chalk uplands near the town have been mined for flint from 

 time immemorial and are riddled with disused shafts, which, in the 

 course of time, become filled up, leaving mere hollows in which grow 

 rank grass and nettles. It was after sweeping several of these hollows 

 that I noticed in my net some remarkably small Jaminm, resembling 

 J. muscorum in miniature. When I afterwards examined the two full- 

 grown specimens obtained, the mouth was seen to be tri-dentate. A 

 day or two later I attempted to procure more examples, but the 

 scorching heat of the sun's rays w.is so great as to make collecting 

 utterly impossible. On reaching home I became convinced that my 

 find was quite distinct from J. muscorum. It seemed to agree in its 

 characters with the continental species, J. triplicata, and I sent it to 

 Mr. B. B. Woodward with a request that he would compare it with 

 typical specimens of the latter. He and Mr. E. A. Smith kindly 

 complied and al)3olutely confirmed my tentative diagnosis. 



There still remained one point to clear up. Gwyn Jeffreys in his 

 "British Conchology" mentions a variety of Pupa marginatavi\\\c\\ he 

 considered identical with the Pupa bii^ranata of Rossmassler. It 

 seemed necessary to find out what this Pupa marginata var. bigranata 

 of Jeftreys really was. Dr. Dall of the U.S. National Museum at 

 Washington kindly searched the Jeff'reys' collection and wrote as 

 follows: — "In the Jeffreys' collection there is a fine lot of /*. bigranata 

 Rossm., and another of P. triplicata Studer, marked 'Burgundy.' 

 There is only a single specimen, mounted on a slip of card marked 

 *var. bigranata'' (of Pupa marginata). The locality of the English 

 '■bigranata'' is given as Richmond. The triplicata Studer is a smaller 

 shell by a good deal, smoother, and lighter coloured than the (also 

 Burgundian) bigranata. The English specimen is a little weathered, 

 but it agrees with P. triplicata and ?iot with P. bigranata Rossm , so 

 far as its general form and size are concerned. Some of the P. tripli- 

 cata seem to agree in the armature of the mouth with the English 

 specimen, though we have none labelled var, bidentata. Without 



