﻿PLANORBIS.— Plate XII. 



Species 101. (Fig. a, h, Mus. Brit.) 



Plaxorbis Isaf.el. Pla. testa parvir, tioiu'dl, nltil, 

 dnj'ArnV, frrnuji'tira, Icevigata ; siiiril jmn-,'!, suli- 

 coiiij'li(,itif,: : ,n,fj(ictihus trihus, nw/in'tiiiariili.^-, 

 .iiipenii siilirrnijiilat'is, tum declivihiis : vltiiiin 

 mac/tio, jirope apertumm ex^anso ; disco wferiori 

 umbilicato ; aperturd angiistd, semilunan, margine 

 siiperiori sinuatim prodiicto. 



The Isabel Planorbis. Shell small, tumid, high, 

 dextral, ferruginous, smooth ; spire small, rather 

 flat ; -n-horls three, rather narrow, slightly an- 

 gular above, then sloped ; last large, expanded 

 near the aperture ; lower disc umbilicated ; 

 aperture narrow, semilunar, upper margin sinu- 

 ously produced. 



MoRELET. ? Adams. Genera of Mollusca. 



Hah. v 



Species 102. (Fig. a, h. Mus. Brit.) 



Plaxordis AClES. Ph,. testa parvd, idrinque compla- 

 iiald, alhd, hvvigatd; anfradibus quinis, suhrotun- 

 iJis, siiperne angustiitscidis,{nfernemagis rotimdis; 

 npertiird ohllque ovafd, supra sutnram elevatd. 



The spear Planokbis. Shell small, flattened on each 

 side, white, smooth ; whorls five, rather rounded, 

 i-ather naiTOw above, more rounded below ; 

 aperture obliquely ovate, raised above the 

 suture. 



PoKEO. Meg. Villa. Cat. 184-1, p. 8. 



Hnk Milan. 



Species 103. (Mns. Brit.) 



Plaxorbis Lakgillierti. Pla. testa tnmcato-conied, 

 castaned, aUlweuld, nitenti, iiifra medium sub- 

 jylamdatd, supra declivi ; spird angusiatd, anfrae- 

 tihus trihus, angustissimis, ultimo magna, lumido ; 

 apertiird suhtrigond, manfiiic sii/ieridri fle.viwsim. 



nferiori 



awlahrato. 



Lakgilliert's Planorbis. Sliell truncated-conical, 

 chestnut, rather raised, shining, rather flattened 

 below tbe middle, sloped alxjve ; spire narrow ; 

 whorls three, very narrow, last large, tumid ; 

 aperture rather trigonal ; upper margin flexu- 

 onsly depressed ; lower disc with a nan-ow um- 

 bilicus. 



MS. 



I lab. ? 



Species 101. (Fig. a, b, Mus. Sowerby.) 

 Planorbis veemiculauis. Pla. tesid vlivai-eo-viridi, 

 piiUtd, parvd, de^iirali ; spird planiiiseuld, anfrac- 



iihii>^ ij^iiuix. niliniih's; luiij nsla/is, dsclivibus, infra 

 ninli II III fiiihrriitrii-iisi^, niilniiniidatis ; disco in- 

 frriori Cfiiicarn ,■ apriinri'i suhtrigoild. 



The vekmicular Planorbis. Shell olive-green, po- 

 lished, small, dextral ; spire rather flattened ; 

 whorls five, rounded, narrow, sloped, rather ven- 

 trieose below the middle, slightly angular ; 

 lower disc concave; aperture subtrigonal. 



SOWEEBY. 



Hah. ? 



Shell with a broader disc and more whorls than 

 Planorbis panms, which, from its colour and general 

 form, it resembles. 



