Illustrations of the recent conchology of Great Britain and Ireland, with the description and localities of all the species, marine, land and fresh water

!JO MOLLUSCA. [CONCIIACEA. Shell strong, subtriangular, subcordiform, and moderately com·ex; umbones much turned to the posterior si<le, acule, and approximate, beneath them a large, oblong, deeply impresse<l, longilu<linally striatcd lunulc; wholc surface coverc<l with numcrous, prominent, rou11de<l, transvcrse, narrow ribs, which are rellected at their superior edges, with severa! inequi<listant, remole lines of growth, almost ali of which are provided with vcry fine, intermediate, concentric strioo, which can only be dis- tinctly scen by the aid of a leos; cartilage or posterior sidc with a long, wi<le, hollow space, which is beset with numerous, fine, sharp, obliquely longitudinal striro; externa! surface cream- white, frequently with severa! longitudinal rays of chestnut- colour, ditfering in <legrec oí intensity in various individuals; most commonly, the central onc very broad, and oíten mottled or streaked with zigzag mnrkings; in sorne specimens, however, it is devoid of markings oí any kin<l; insidc white; margin lincly crcnulatecl. Size varying from thrcc-quartcrs of an inch to an inch ami a quarter. This species is met with on almos! ali thc coasts of Ilritain an<I Jrclan<l. 2. VENUS nuaosA, pi. XXXVI, f. 14. Venus rugosa, First Ecl., pi. 20, í. 14 ; Pen11ant, IV, p. 95, pi. !iG, f. 50; Ortygia rngosa, L cach, l\18S., p. 8; Venus Gal- lina, vcw., Montagu, Syn., p. 113 ; Donovan, II, pi. 68, leít harul fi gure; Venus palticfo, Turlon, pi. 10, í. 5. Shcll strong, sublriangular, ancl subcordiform ; umboncs rathc1· promincnt, with an elongatcd lunulc undcr thcm, and a hollow clongatcd spacc 011 thc carlilagc hingc-linc, with fine, obliquely longi tudinal stri:c; wholc surfacc of a uniform rcd- Jish-brown, rarcly crcam-whitc, coverccl by sharp, elevatcd, in- tcrruplcd, lamclliform ribg, which makc thc shcll fccl rough to thc touch; thc intcrvcning spaces coverc<l witli ncarly obsolctc, longitudinal striro; insidc whitc; margin rathar blunt, ami finely crcnulalcd intcriorly. Seldom cxcccding an inch in lcngth. Thi$ shcll bears a slrong allinily lo V. Gallina, but dilfcrs in the form of thc ribs, in bcing providcd with longitudinal striro, :1111I in thc valvcs bcing consiclcrnbly more inílatcd, in propor- tion to thcir sizc. Found in the Friths oí Forth ami Cly<le, ami Dawlish. ;J. VENUS SUI.CATA, pi. XXXVI, f. 12. Ortygici sulcala, First Ed., pi. 20, f. 12; Ortygict P1·i- clc1111,t·imw, Lcach, l\ISS., p. 8; Vc11'lls Galli11a, Turton, Iliv., pi. !), f. 2. Shell subtriangular, snbcomprcssccl , the dorsal side rather pointcd, mo(lcratcly strong; umboncs produccd, much turncd to onc sitie, with an oblong, cordiform deprcssion unclcr them ; of a palc crc:un-whitc, with írcqucntly from two to four rays oí a dccp chcstnut-brown, inlcrruptccl by thc ribs, and thc intc rYCning spaccs oftcn mottlcd ali over with thc samc colour; frcquc111ly dcslitulc oí radiations or markings; wholc surfacc co,•cl'Ccl with many trans,·ersc, nearly cquidistant, somcwhat remole, clivatcd ribs, ami thc intcrvcning spaccs smooth; insidc whitc; margin blunt, ami fincly crcnulatecl. Length scldom more than thrcc-quartcrs of an inch. Found on thc Dcvonshirc coast; ami also in Lough Strang- fonl, Ircland. Distinguishcd from thc two formcr specics, by its rcm()lC ribs ami more triangular form, which it assnmcs in its carlicst stagcs oí t;rowth; aud it is much lcss vcntricosc than cithcr. 4. VENUS C0STATA, pi. XXXVI, f. 13. Ortygict costata, F irst Ed., pi. 20, f. 13. Shcll suborbicular, subcompresscd; umboncs somcwhat ob- tusc, and subccntrnl; wholc surfacc of a palc rcddish-brown, and coverccl by remole, rather clevatcd, transvcrsc, whitc ribs; insi<lc white ; margin crcnulatcd. Diffcrs from any of thc prcce<ling species, in its more orbicu- lar form, and in thc character of thc ribs. Foun<l by me at Scaton, Northumbcrland. 5. VENUS LAMINOSA, pi. XXXVII, f. 1'1, 15. Ortygia subconlata, First Ed., pi. 19, f. 14, 15 ; Monta¡:u, Sup., p. 38; Venus la111i11osa, Laskcy, \Vernerian Mcm., I, p. 384, pi. 8, f. 16, lG. " Shcll oYatc, with numcrous conccntric lamina! ridgcs, very littlc rcllcctecl, ami not quite regular nor cquidislant, but so thin as to be almost mcmbranaccous; bctwccn thc ridges, about. thc umbonal rcgion, whcre a natural dccortication has takcn place, it is finely striatccl in the longitudinal dircction, which shews that younger spccimens are more gencrally fur- nishccl with such striro, but in thc only large specimcn wc haYc had an opportunity of examining, scarccly any such markings ,,·ere obscrved but whcrc thc old shcll hacl bccn supcrficially scparatcd; umbo pointccl, much reclinecl to onc siclc, bcncath which is a broacl cordifon11 deprcssiou; but neither this, nor thc cartilagc slopc cliffcrs in colour from the rcst of thc shell, which is wholly of a dirty white; insicle whitc; hingc furnishecl with four tccth in cach ,•alYc, but thc outcr onc abo,•c the cordiform cleprcssion in onc Yall'C is obsoletc, or fonncd only by a cavity for thc rcccption of thc corresponding looth in thc oppositc valvc; margin finely crenulatcd. Lcngth somcwhat more than an inch; brcadth about an inch ami a quarter."- 1lfontag11. Saicl to havc bccn dredgc<l off thc ! sic of l\fay, Frith of Forth, by Captain Laskcy. 6. VENUS vEnnucosA, pi. XXXVI, í. 16.'-• Clausilw vc1·1·11c:os11, First Ed., pi. 20, f. 16; Vc11us vc1·1·11cos11, Poli, II, p, XVIII, pi. 21, f. 18, 19; Donovan, II, pi. <IG; l\fon- tagu, p. 112; Flcming, p. 4•16; Turton, Iliv., Jl· 1'10; Ve11us Ei'!}cina, Pennant, IV, p. 9-1, pi. 54·, f. 48, Shcll suborbicular, corclifonn, slrong, thick, convex, sublrun- catc<l at the lowcr anglc oí the dorsal sidc; umboucs much inllcxcd anteriorly, sharp-pointed, ami approximate, bcncath them a largc, clongatccl, cordiform, <lccply dcfinccl lunulc, fincly striatccl longi tudinally, with thc scam twistcd; wholc smfacc covcrcd with strong, clcYalecl, l rans,•crse, rnricosc, conccntri- cally slrialcd ribs; thc warts bcing largcr, and more clcvatccl 011 thc posterior si<lc; ali thc inlcl'\'cning furrows with broacl, wide-set, longitudinal stri,c, giving thc shcll a Ycry rugosc aspcct. ; cartilagc slopc of the lcft vahe inllcctctl; a clccp, clon- gated, obliquely striatcd spacc cxtcncls from thc nmboncs 011 the cartilagc slopc, to thc subtruncature of thc rnl\'CS; colour oí a dirty whitc, or dull rusty-brown; insidc smooth, whitc, with a ílat, thickcnecl, crenatecl margin. In thc young con<lition, thc ridgcs are more pcrfcct than in thc adult, with thc intcrsticcs fincly crcnulatcd. Fouucl on thc coasls oí Conmall, D e\'011, Dorscl, Kcnl, ami Norlhumberlancl; as also Dublin llay, Porlmarnock, ílalbrig- gin, ami othcr localitics, Irclan<l.