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

LITIIOl'IIAGI.] MOLLUSCA. 103 smallcr bcing, howcvcr, a litllc strongcr; insiclc ycllowish or crcam-whitc, with numcrous, glossy, circular spots; pallial im- prcssiou with a largc sinus, placee! lransvcrsely, bul does not intcrrupt the pnllial impression bclow, as it rises al thc acumi- nntcd sidc. Found iu Bantry Bay, Killough, County of Down, ami other places 011 thc coast of Ircland. 7. PS,n!MOlllA LASKEYI, pi. XXXIX, f. 32. Ps11mmobi1t L11skc!Ji, Turton, 13i1·., p. 8!); Flcming, p. 438; Telliiw L11ske!Ji, :Montagu, Sup., p. 28, pi. 28, f. 3. Shcll transvcrsely Qblong-ovalc, smooth, rathcr strong; um- bones not quite central, ancl obtusc, harclly inílcctecl; si<lcs <lis- similar, onc rounclcd, the othcr obtuscly pointccl and obliqucly subtruncatecl; colour purplish-whitc; covcrecl with an olivace- ous-yc\low epidermis; insiclc purplc, smooth, whitc roun<l thc margin, alHl clestitute of thc crcnul:-e; one valrc with thrcc approximate, subbifi<l tccth; thc margin channclled from thc tecth almos!. to thc cm\ of thc longcr siclc; on thc other sidc of thc tecth thc margin is rcplicatccl, or fo\<lc<l back to thc connccting cartilagc, to which it is afTixcd ; thc oppositc mire with only a single tooth, which locks in bctwcen thc teeth of thc othcr valve, thcsc are reciprocally aclmittc<l into a cavity on cach sidc in this valve, which is <lcstitutc of a channcl on thc margin. Lcngth half an inch; brea<lth thrce- quartcrs. Discovcrcd, by clreclging, in thc Frith of Forth, by Captain Laskey. FAMILY V.-LJTIIOPHAG(. Shells which borc into clay, woocl, and other substanccs; des- titule of acccssory pieccs; more or lcss gaping at the anterior side; ligamen! situatc exleriorly. GENUS 26.-SAXICAVA.-Lamarck. Shcll transverse, irregular in form, generally oblong, incqui- lateral, subequivalve, gaping antcriorly; ligamen! exterior; two lateral, muscular impressions in each valve; pallial impression interrupted, but not sinuatcd; hinge, in the young conclition, with somclimes two or thrce minute, obtuse, mostly inclistinct, cardinal teeth, which become obsoletc in thc aclult; two cleep muscular imprcssions in cach valve; pallial impression entire. l. SAXICAYA HUG0SA, pi. XLVII, f. 14 and 16, ancl pi. XLVIII, f. 15, 16. Pholabia n1gosa, First Ed., pi.!), f. 15, ancl pra:cisa, f. 16; Lcach, MSS., p. 5; Sa:1:icavct 1·ugosct, Lamarck, V, p. 501; Tmton, I3iv., p. 20, pi. 2, f. 10; Forbes, p. 56; Ilicitellct 1·ugosa, Fleming, p. 461; 11'l!Jlilus 1·ugosus, Pcnnant, IV, p. 110, pi. 63, f. 72; Montagu, p. 164; Dono1•an, pi. 141 ; Maton and Rackett, p. 105. Shel\ transvcrsely oblong-ovate, somewhat inllate<l; ancl gaping at onc sicle; umbones small, obtusc, ancl situatc near to thc anterior sicle; posterior sicle always rounclecl; anterior si<lc gcncrally subtruncatecl; surface brown or clull yellowish-white, with irregular, rugged, concentric wrinklcs; insicle whitc. Fig. H.l, pi. XLVIII, is thc variety Jlf!)tilus p1·a:cisus, Mon- tagu, p. 165, pi. ,1, f. 2; Maton ancl Rackctt, p. 105. This spccies is liable to grcat varicty in its externa) form, as will be scen by our various figures, bcing somctimes subquacl- rangular or subcylinclrical, frcqucntly much distortcd ancl wrin- klcd, at others almost smooth, It is a frequcnt inhabitant of the roots of the largc alga:, ami cvcn pcnctratcs thc lmrclcst limestonc; it is met with on almost ali the coasts of Britain ami Irclan<l. Fig. 16, pi. XLVII, is the varicty callcd Sa.dcaw Pholacfit, Turton, lliv., p. 21, pi. 2, f. 11; all(I fig. 1,1 a still more globular form of thc same species. 2. SAXICAVA PUlll'UltEA, pi. XLII, f. 2!), 30, 31. llf!Ja pu17J10-ca, Montagu, Sup., p. 21; Agina p1117mre11, Turl 011, Biv., p. 54, pi. ,1, f. !). Shcll transversely oblong-ovatc; umboncs purplc, placed con- si<lerably to onc sicle, an<l inllectcd towards thc shortcr ell(l, which is roun<lccl; the anterior ene\ obliquc.>ly truncatcd; i11\"estcd with a glossy, crcam-white epidermis; unclcr which !he shell is pure whitc, :me\ covcred with irregular, Lransl'ersc ,-triro; hinge with a single, obscurc, crect tooth in each vah•c, and slightly clcft, which penetratc c:ll'itics in thc opposite valre. Lcngth about an eighth of an inch; brea<lth a quartcr. _ Takcn in <leep water, amongst corallincs, on thc Dcvonshirc coast, by Coloncl Montagu ; and drcdgccl at Torbay, by Dr. Turton. GENUS 2í.-l-hATELI.A.-Dauclin. Shell trans\'erse, incquivalvc, incquilateral, gaping al tite superior margin, or anterior siclc; umboncs small, bhmtcd, placed considerably towanls thc posterior sidc; ligamen! exter- na!; hinge with a small, il1 <lcfined, single tooth in one rah·c, inscrted between two obscuro oncs in thc other; dcstilutc of lateral tccth; two large ancl clccp muscular impressions in cach valvc, th1Jse on thc anterior sidcs largcst, wirh a longnc-likc prolongation from the siclc, pointing inwar<ls; pallial imprcssion entire. ]. HIATELl,A MINUTA, pi. XLVII, f. l. Solcn 111inut11s, First Ed., pi. 13, f. 1; Lamarck, V, p. 453 ; i\Iontagu, p. 53, pi. 1, f. ,1; llfaton ancl Hackctt, p. 47; llirttelltt 111i11uta, Turton, 13iv., p. 24; Iliatclfo m·ctica, Flcming, p. 46 J ; Sa.1:iccwa rugosa, young shell, F orbes; Cormnyct .vpi11osa, Leach, MSS., P· 5. She\1 transvcrsely subovale, rugose, slightly inílate<l; umbones placed towar<ls the posterior side, which is roundcd ; anterior side subtruncatcd; one valve smaller than thc othcr, cach pro- vicled with two rows of concavc spincs, situate on thc anterior sidc, cmanaling from the u_mboncs, an<l tcrminating on thc siclc, the superior row running parallcl with thc cartilagc linc, thc other running cliagonally clownwarcls; undcr val ve projccting slightly ovcr the othcr, exccpt al the shortcr si<le; surfacc of a palc brown, or ycllowish-white; insi<lc smooth, glossy, whitc, somctimes tingcd with ochre-yellow. Found on most of thc Ilritish ancl Irish coasls, burrowing in harcl limcslone rocks, clay, an<l othcr substances. 2. HIATELLA 00!,0NGA, pi. XLVII, f. 14. Hiatella oblo11g11, Turton, Biv., p. 25, pi. 2, f. 13; Hiatell11 arctica, Fleming, p. 461. Shcll transrcrsely oblong-ovatc; posterior sicle roundccl; an- terior sidc subtruncated, slightly wrinklcd transvcrscly, rather promincnt, ami destitute of spincs; umboncs placed ncar the posterior siclc; surfacc of a palc brown, or yellowish-brown;