Mr. J. G. Jeffreys on British Mollusca. 48 



cardinali et fovea ligamcntali fere ut in P. gramdata ; long. -^, 

 Int. ^'y uncioc. 



Oiily a single valve of this remarkable shell has occurred to me, in 

 Shcthuul sand. It tliffers from the young of Poromya yramduta 

 in Ibrni, tuxturc, luiil tlie absence of the scabrous markings which 

 distinguish that s|)ecics. I searched in vain the collections at the 

 Britisli Museum and of !Mr. Cuming for its counterpart. I may be, 

 perhaps, considered very rash in j)roposing to found a uew species 

 on a single valve ; but I, of course, do so only (fiunttim valeat, and 

 would observe, that science has ol'ten benefited by the publication of 

 any fact, however incomplete, the hiatus being afterwards filled up 

 by further researches and discoveries. 



Thracia villosiuscula, i. 224. Arrau I., Galwav (Barlee) ; Cork 

 {jrright). 



Diodonta Barleei, n. s. PL II. fig. 2. 



Testa triangularis, subinrequilatera, compressa, antice productior, 

 postice sul)truncata, hyalina, nitida, fere glabra ; marginibus late- 

 ralibus utrinque dcclivibus ; margine ventrali rotundato ; umbo- 

 nibus prominentibus, rectis, nucleatis ; lunula nulla ; ligamento, 

 cardine, et dentibus ut in D.fragili ; long. -^■^, lat. -^ unc. 



About a dozen specimens of different sizes were taken by ]Mr. Barlee 

 in dredging off Arran Isle, on the west coast of Ireland. At first I 

 suspected them to be the fry o{ Diodonta fragilis, which, is not uncom- 

 mon in the same locality ; but, on comparing them with an umbonal 

 segment of the same size, taken from a specimen of the latter species, 

 I perceived that they would differ from the young of D. fraydis in 

 being more compressed and obtusely triangular, and in the ventral 

 or front margin being more rounded, besides being quite destitute of 

 the transverse ribs and longitudinal grooves of that species. It 

 should also be observed, that the fry of Lucina Borealis show most 

 distinctly the transverse and irregular striae or wrinkles, and are of 

 the same relative shape as adult individuals. The present species 

 bears some resemblance in form and size, but not in markings or 

 dentition, to Montacuta substriata. 



Scrobicularia piperata, i. 326. Barmouth. 



Astarte triangularis, i. 467. Arran Isle, Galway {Barlee). 



Cardium nodosum, ii. 22 {C. papdlosxim of Philippi being the 

 older name). Barmouth. 



C. Succicuni, ii. 33 ((7. minimum of Philippi being prior in date, 

 and more appropriate). Arran Isle, Galway {Barlee). 



Lucina Boreali.^, ii. 46. Barmouth. 



Montacuta ferruginosa, ii. 72. Barmouth. 



M. bidentata, ii. 73. Barmouth; Shetland sand. 



Kellia (Poronia) rubra, ii. 94. Barmouth. 



Lopton nitidum, ii. 92, and var. convexum, ii. 102. Arran Isle, 

 Galway {Barlee). 



L. Clarkise, iv. 255. Arran Isle, Galway, and Fowey (Barlee); 



