﻿P L A N E B I S. 



Plate II. 



Species 8. (^Iqs. Sowb.) 



Planohris NAUTiLEus. Pill, testd alhidd, parvd, suh- 

 dejtrcssd, anfractihtis quatuor, rapide erescentibiis, 

 liris conteis, ad marginem spi'twsis aniiulatis, ul- 

 timo disjuiicto, disco superiori ■plamdato, anfracti- 

 hiis rolnudo-depressis ; disco inferiori lath tisque 

 ad apicciii uvihlUcato. 



The NAUTiidin Planoems. Shell whitish, small, 

 rather depressed, whorls four, quickly enlargiug, 

 i-idgcs horny, aunulated with horny ridges spin- 

 ous at the margin, last disjoined, upper disc 

 flattened with round-depressed whorls ; lower 

 disc broadly umbilicatcd as far as the apex. 



LiNN.EL's. Systema Natura>. 



Flaiwrbis imhricntu.-<. jMiillcr. 



rianorhi.t crislatus. Draparnaud. 



Hah. Franco, Groat Britain. 



Species !•. (Fig. a, h, Mus. Sowb.) 



Plaxoeris contoktis. Phi. frsid fiilvd, mediocriter 

 depressd, sajienii: plauidatd, infra angulatim urn- 

 hiUcatd ; aiifnictilius senis, Icnte cresceiililiiia, 

 anijnsiis, siipcrnc rniundatis, iiifrd ad margiui'in 

 innbllici iDiqiihili)!, umhiliio angusto, prnfnndu ; 

 apiiinrd r^miil minr!. 



The evhn-vvii(iri,eii Planokiu.?. Shell fulvous, mo- 

 derately depressed, flattened above, angularly 

 umbilicatcd below ; whorls six, slowly increased, 

 narrow, rounded above, angular at the edge of 

 the umbilicus, umbilicus narrow, deep ; aperture 

 semi-lunar. 



MuLLER. Drap. ilol. PI. I. f. ;_!0-ll. 



Planorliis cras.oi': 'f 



Planorhis vmhilir,:fiig ? 



Hah. England, France. 



Species 10. (Fig. a, h, Mus. Sowb.) 

 Plakokbis gI/Aber. Phi. testd subaurantid, ■tiitc-iili, 

 aUiitscidil, anfradihus trihus, rapide creseenfihnx, 

 ultimo lata, siiperne suhplanulatis, disco superiori 

 qiiani iiiferior angiistiori, disco inferiori jilaiin, 

 tuherculato ; apertiird ohliqud, lahio externa con- 

 vexe ohliqno. 



The smooth Planorbis. Shell somewhat orange, 

 shining, rather elevated ; whorls three, quickly 

 increasing ; the last wide, i-ather flattened at tlu^ 

 top, upper disc a little narrower than lower ; 

 lower disc flat, tuberculated ; aperture oblique, 

 outer lip convexly oblique. 



Jeffreys ? British Mollusca, &c. 



Planorhis Icevis. Alder. 



Hah. Penzance, Falmouth, Swansea, Belfast, &c. 



Species 11. (Fig. a, h, Mus. Brit.) 



PlaXOKBIS CAMPANULATUS. Fla. testd altd, tcuilissinir 

 ohliqui' liratd; arifractihus senis, rapidi; crcseeidi- 

 bus, externo magiw ; disco superiori profunda e.c- 

 cavato, anfraotihus intemis ccelatis, externis ro- 

 tundis, ultimo versus aperfnram coniracto, twin 

 r^rpansn; disc iuf.ri..ri .nfrartlh.s pnpr .nhrram 

 avgidalis: aprrhn.! s„hp,,rifn:,i, c.rj.u,s,!, sn- 

 perni elevatd, iiitiis nmtrarld. 



The bell Planorbis. Shell high, finely obliquely 

 ridged ; whorls six, rapidly increased, outer one 

 large ; upper disc deeply hollow, inner whorls 

 hidden, outer rounded, last contracted towards the 

 aperture, then expanded ; lower disc with whorls 

 angular near the suture ; aperture rather pyri- 

 form, expanded, raised above, contracted within. 



Say. Journ. Am. Soc. Phil. Vol. II. p. 166. 



Hah. Newport, Iowa, U.S. 



Species 12. (Mus Sowerby.) 



Planorbis carinatus. Pla. testd dep)ressd; anfractihics 

 quaternis, extics paido infra medium acute 

 carinatis ; idlimo lafo ; disao superiori excavato, 

 anfractihus convccis ; disco inferiori magis con- 

 vexo, anfractihus suhphinidalis. 



The keeled Planorbis. Shell depressed; whorls 

 four, sharply keeled on the outer side a little 

 below the middle ; last broad ; upper disc hollow, 

 whorls convex ; lower disc more convex, with 

 rather flattened whorls. 



MuLLEE. Drap. Mol. PI. 2, f. 13, 14. 



Hdix planorhis. Linnasus. 



Planorbis planatus ? 



