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

lN\'OLU'l'E,] MOLLUSCA. G3 Shcll orntc, suhmembranaceous, greatly depre~setl, with a single, minute \'Olution; wholc surfacc concenlricallr wrinkled; extcrnal surfacc COl'Cred wilh a sill'ery, iridescenl epidermis, nxhibiting l'arious nacrecl melallic hncs, uf blue, pink, ami yel- low; aperlmc cxtcnding thc wholc lcngth of thc shcll, l'cry glossy inlcrnally, ami has umlulations corrcspomling with thc wrinklcs of the outsidc. Lenglh an inch and a half; and up- wanl,; of an inch in brcallth. This species is more memhrauous thau P. plumula, some- what more conl'ex, with thc rnlution ami apex more prominent. Firsl found on thc csluary of Kingsbridie, by Colonel Mon- tagu; it has since bccn mct with on sereral of the coasls of Brilain all!I Ireland. F,nm,Y VI.-P11Y1,1,ID1ACEA. The branchiro are siluatecl bencalh the margin of the mantle, in n longituclinal series around the body. Animals rcspiring in water. GENUS 16,-PATELLA.-Linn:cus. Shell ovate or oblong, more or less of a conical form, desli- tule of spiral convolutions; sometimes, although rarely, pyra- midal; apex rarely central, generally placed auteriorly, with its apex inclined towards the head of the animal; concave within, ami the margin enlirc; muscular impressions distinct, and same form as the shell, placed about half way betwixt the summit and thc margin, interrupted in front where the head of the animal is situated; externa! surface striated, or ribbcd in a variable manner, from thc apex lo thc base; in lhe taller case, lhe margin is variously dentated, slellatcd, or crenulated. l. PATELl,A VULGATA, pi. XX, f. 5, 12, 14, 15, and 17. Patcllct vulgata, First Ecl., pi. 37, f. 5, 12, 14, 15, ancl 17; Linné, Syst., p. 1258; Lamarck, Syst., VI, pt. 1st, p. 331; Fleming, Brit. An., p. 286; Ib., Ency., p. 65; Brown, Eacy. Brit., P· •165; Ib., Wcrnerian l\1em., II, p. 532; Montagu, p. 475; Forbes, p. 36; Maton ami RackeU, p. 229. Shell subconic, oval; vertex obtuse, nearly central, or siluate nearest lhe smaller cnd; externa! surface with numerous, cli,,er- gent ribs, or stri:c, emanat.ing from the apex, ami terminating on the margin, which is cither plain, or stellated ancl inclented, as lhe shell may be ribbcd or striated respectively; externa! colour various, most frequently of a clull, dusky brown, recldish- brown, or dirty yellow; insicle extremcly glossy and transparent, variable in colour, frequently iriclescent, either plain, or exhibit- ing beautiful raclialions of blue, purple, or browu. The Patcllct vulgatct is liable to great variation in its clegrec of elevation, general form, and externa! appearance, depending, in a grcat measure, on the fineness or coarseness of its striro, and the number and elevalion of its ribs. In some it is covered with fine, close-sct, racliating stri:c, rrossecl by irregular, inequi- distant, concentric stri:c, or lines of growth; in others it is slrongly ribbecl, producing an indented margin; lhese ribs are always irregular in number, and the interstices wilh clivergenl slri:c. The interior is also subject to much variety of colour; bcing horn-r.oloured, bluish-white, or yellow, and either plain, or with radiations of diffcrent hues; often with a clark brown, or blackish, large, regular mark in thc middle. The following are tho more promincnt varieties: Va1'iety l. VULGATA, pi. XX, f. Ii. Longituclinally st,•i- atecl, 01· witlt 1·ibs br1t sliglttly clevcloped. Pennant, Brit. Zoo!., IV, p. 142, pi. 89, f. 1'15; Donol'an, pi. l •l, first fig. V111"it:ty 2. CoMMUNIS, pi. XX, f. 15. Sltell de¡wcssed, witl1 shm')>, s11Úm1"i11atccl, fr1·cgulm· ,·ibs, both -in si:::e and nmnber, p1·ocluci11g an acutely angulm·, fr1·cg11lcw mm-gi,1 ; bctween tlic 1·ibs tlu: shclt ·is oftcn rndictlcd with brow11 01· JIU1'plc. 1'his is tlw most com11w11 fonn. Patcllct clcprcssa, Pennant, p. 142, pi. 89, f. 146; Da Costa, p. 3, pi. 1, f. 1, 2, allCI 8 ; Donornn, pi. 14, ali the figures bnt the first. Vm·icty 3. ALilUMENA, pi. XX, f. 12 ami 1'1. Shell de- J>1'CSscd; outsidc with nu111c1"011s, nca1'l!J eqrticlista-nt, divc1-gc11t, rounclecl, but ratlwi·Jlat ribs, blwrt al tliei1· c.t·lel'lwl cnds, mul always p1·otnuli11g consiclcrably bcyo11d the 1/lct1'/¡ÍII, the inte1·- sticcs with strong aml Tathc1· regula,· st1·ia:; gcnemllg oJ et ycllowishfawn-colo111', aml oftcn witltfromfi>rw lo si.t· concc11- ti-ic Úall(ls of bw·nt tcn·a-sicnna colou1'; insicfo oJ et pale bluish or ycllowislt-wliitc, tlic gla:::ing tltickenccl, subopar¡rw, all(l not ve,'!/ gloss!J, liaving much thc appcctl'ancc qf albumen. This varicly is very easily clistinguishecl in ali the stages of its growth. I first noticed this very beautiful \'ariety on rocks at Color Cots, ncar Tynrmouth, Northumberlancl, in 1810, all(I T. ·w. ·warren, Esq., of Dublin, has latcly furnished me wilh a complete series from Portmarnock, Irelancl. Vai·icty 4. CoNICA, pi. XX, f. 5. Sltcll conical; i ts hcight being nca-rlg cr¡ual to its lcngth; u:ith st1·011g, ? 0 11diati11g, blw1t, 1·owulccl 1·ibs, p1·ot1·11cli11g brtt littlc bc!Jond tite ?lwrgin, which ú, in conscquc11ce, but slighll!J uiufolou$. This varicty prcvails on lhe coast near Damborough Castlc, and 011 sorne rocks al Holy Jslancl, Norlhumuerland. IL is also met with in other places of England ancl Irelancl. I noliced il in the latter country near Balbriggan, and at Killough, Counly of Down. 2. PATELLA VIRGINEA, pi. XX, f. 1, 4, ancl 6. Patella vii-gine<t, First Ecl., pi. 37, f. 1, 4-, and 6; Linn. Gmelin, 3711 ; Patcll1t tcssulctta, Müller, Zool. Dun., pi. 12, f. 4, 5; Forbes, p. 36; Matou ami Hackett, p. 234; Brown, Ency. Brit., p. 466; Ib., Wernerian Mem., p. 533; Fleming, p. 287; Patell1t pana, Da Costa, p. 7, pi. 8, f. 11; Donovan, pi. 21, f. 2; Montagu, p. 480; Turton, I3rit. Fau., p. 197. Shell lhin, oval, subconic, subdcpresscd; gcnerally covere<l with a grayish epidermis; beneath which thc surfacc is gene- rally beautifully radialed with alternately broad and narrow pale brownish-red or pi11k, frequently commingling in a catinaled manner, somctimes only visible near lhe margin; longiludinally strialccl, and crosscd concentrically with ncarly obsolele wrin- kles; vcrlex acute, siluale ncarcst one end; inside smoolh, glossy, of a rosy or purple hue, and in sorne instances whitc. Length upwards of three-cighlhs of an inch ; brea<llh a quarter of an inch; height not quite so much. lt is found but rarely half an inch long. A local species, found in Falmouth Harbour, Whitesand Bay, Cornwall; Salcomh Bay, Devon5hire; the coasts of Northum- berland ancl Durham; the Friths of Forth ami Clycle; thc l\1anx coast; anc! severa! shorcs of Ireland, as Dublin Bay, Porlmarnock, Longh Strangford, and Coye of Cork.