Mr. J. G. Jeffreys on British Mollusca. 43 



cardinali et fovea ligamentali fere ut in P. granulata ; long. ^, 



lat. -J^ uncise. 



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

 Shetland sand. It differs from the young of Poromya granulata 

 in form, texture, and the absence of the scabrous markings which 

 distinguish that species. I searched in vain the collections at the 

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

 perhaps, considered very rash in proposing to found a new species 

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

 would observe, that science has often benefited by the publication of 

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

 by further researches and discoveries. 



Thracia villosiuscula, i. 224. Arran I., Gal way (Barlee) ; Cork 

 (Wright). 



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



Testa triangularis, subinsequilatera, compressa, antice productior, 

 postice subtruncata, hyalina, nitida, fere glabra ; marginibus late- 

 ralibus utrinque declivibus ; margine ventrali rotundato ; umbo- 

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

 cardine, et dentibus ut in D. fragili ; long. ^V, lat. -^L 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 oi Diodonta fragiliSiVfhich. 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. fragilis 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. papillosum of Philippi being the 

 older name). Barmouth. 



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

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



Lucina BoreaUs, ii. 46. Barmouth. 



Montacuta ferruginosa, ii. 72. Barmouth. 



M. bidentata, ii. 7^. Barmouth; Shetland sand. 



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



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

 Galway {Barlee). 



L. Clarkise, iv. 255. Arran Isle, Galway, and Fowey {Barlee)', 



