HELIX.— Plate CXXXIX. 



1'keikkek, Pro. Zool. Soc. 1850. 

 Ualj. Islantl of Purto .Siiiito, Jfadeiras. 



.\ pcrlcctly white shell, enciiclctl beneath with n fuint 

 subtranspaient thread-like line and obscurely keeled round 

 till' middle. 



Species S78. (^tus. Cumiug.) 



Helix obtecta. Hel. tesid iimbilicalu, depreiad, mperni 

 planiuscidd, basi convem, soUdiusvuld, eroHO-scrobicuh- 

 td, snbgramilatd, sorcJidi fitscesceiili' ; anfrdctibiis qiiiu- 

 que, i.-o/wexis, primin immersii, nfquentibuK iuryidis, 

 idiimo mperni angulato, aniici dejlexo ; umiilico me- 

 diocri, pervio ; operturd wbcirculari; pemtomalu 

 coidiniio, vix expanso, iutus nubiiicra-isalo. 



The covered Helix. Shell umbilicatcd, depressed, 

 rather flat at the ii})per piirt, convex and rather solid 

 at thq base, erodely pitted, subgranular, dull brown- 

 ish ; whorls five, convex, the first immersed, the fol- 

 lowing swollen, the last angled at the upper part, de- 

 flected in front ; umbilicus middling, open ; aperture 

 nearly cii'cular; lip continuous, a little expanded, 

 slightly thickened within. 



Lowe, Faun. Mader. p. 47. pi. 5. f. 20. 



Hah. Islands of Baxo and Porto Santo, Madeiras. 



Characterized in cluef measure by its roughly pitted 

 surface. 



Species 879. (Mus. Cuming.) 



Helix semicostulata. Hel. iesld umbilicatd, depressd, 

 stibtuH convi'jcd, subdiscoided, soVuK corned, livido-ci- 

 nered, nitetile, .supra IfiiUK utriald, infra heciijaid ; 

 spird plano-convexd; anfractibus quinque, phniitsculU ,- 

 aperturd ubliqw; Imiari ; perislomale simplici, acuta. 



The half-kibbed Helix. Shell umbilicatcd, depressed, 

 convex beneath, somewhat discoid, solid horny, livid- 

 ash, shining, tliiidy finely striated above, smooth 

 below ; spire flatly convex ; whorls five, rather flat- 

 tened ; aperture obliquely lunar ; lip simple, sharp. 



Heck, Pfcilfcr, Moiiig. llelic. viv. p. -Via. 



Hab. Island of Grand Canary. 



A livid-ash homy species, with somewhat of a Planorbis- 

 aspeel. 



Species 880. (Mus. Cuming.) 



Helix Lyelliana. Uel. testa und>ilicatd, deprcsso'cu- 

 nica, lolUliiuculd, aciitisaiuie cariiiatd, arcuatim ienui- 



tlrmtd, ftuceKetde, castaneo foKialn et tariegata ; 

 spird obtiisd ; aufrnrlibm orlo, planalin; aperturd 

 litnato-circulari ; peri)itomate simplici, expaino, margi- 

 tiibus callo teiiui jnnctit, columellari rejlexo. 



Lyell's Helix. Shell umbilicatcd, dcpressly conic, rather 

 solid, very sharply keeled, uicuately finely striated, 

 light browiiisb, banded and Tariegatcd with chest- 

 nut; spire obtuse; whirls eight, flattened ; aperture 

 lunar-circular; lip simple, expanilcd, margins joined 

 by H thin callosity, cohinn^Uar margin reflected. 



Lowe, Ann. and ALig. Nat. Hist. vol. ix. p. 117. 



llab. Island of Descrte Grande, Canaries. 



Curiously allied to the H. lMt<rri type of the Philippine 

 Islands. 



Species 881. (Mus. Cuming.) 



Helix bifko.ns. Ilel. ttsid umbilicatd, orbiculari-con- 

 vexiiisculd, subcarinatd, tenia, nitidd, corneo-tirescente, 

 infra latiusculd, obsoleti^ utriatd, supra costulato-stri- 

 atd; spird vix elevald ; auturd distincld, impreud; 

 anfractUtus scptem, lente accreacenlibm, ultimo basi 

 convexo ; nmbilico parco, cylindracm, profunda ; aper- 

 turd lunari ; peristoniate simplici, tenui, acuta, iiUus 

 latissinii'' albo-labiido. 



The Two-FACEi) Helix. Shell umbilicatcd, orbicularly 

 rather convex, slightly keeled, thin, shining, homy 

 greenish, rather smooth beneath, obsoletely striated, 

 rib-like striated above ; spire but little raised ; suture 

 disliuet, impressed ; whorls seven, increasing slowly, 

 the last convex at the base; umbilicus small, cylin- 

 drical, deep ; aperture lunar ; lip simple, thin, sharp, 

 very broaiUy white-edged within. 



Lowe, Paun. Mader. p. IG. pi. 5. f. IS. 



Hab. Madeira. 



Of regular circular growth, rib-like striated above, and 

 smooth below. 



Species 882. (Mus. Cuming.) 



Helix LENIS. Uel. testd lati umbilicatd, glaboso-depressd, 

 tenerd, striatd, diaphand, oUcaced aut rufescente, iii- 

 tindv ; spird vix elevatd, oblusd ; anfractibus quatuor 

 ad quinque, convfxiusculis, ultimo subrotundata ; aper- 

 turd luuari-circuhri, parviusculd ; peristomate recto, 

 simplici, acuta. 



The smooth Helix. Shell broadly umbilicatcd, glo- 

 bosely depressed, thin, striated, diaphanous, olive or 

 reddish, shining ; spire but little raised, obtuse ; 

 whorls four to five, rather convex, the last somewhat 



