HELIX.— Plate CLXXFV. 



liEXSON, Ann. and Mag. Nat. Hist. 1851, vol. vii. p. 105. 

 Hab. Cape of Good Hope (iu sandy tracts, in Hunt and 

 False Bays) ; Benson. 

 A minute Cycloitoina-MVa species, of a dull straw-colour. 



Species 1181. (Mus. Benson.) 



Helix vorticialis. JM. tenia unibiUcatd, suidiscoided, 

 supenii depresao-plaiiatd, ieiiui, riifescenle- corned ; 

 spird concaviuaculd ; sutiird profunda ; aiifracliius 

 qualiior, aiiffualii, concexii, confertlm radiato-plicatis, 

 penuUimo promiiienfe, ultimo non deacendente, a latere 

 nubcompresso, wbtus valde convexo ; umbilico lato, pro- 

 fundo, marijiiie submiijulato ; aperlurd verticali, rotitn- 

 dalo-lunari, alliore quam lata; peristomate siinplici, 

 redo, viaryinibui via convergentibus, callo tenuissimo 

 juttclis. 



The wiiiitLPOOL Helix. Shell urabilicated, subdiscoid, 

 clcpressly flattened at the upper part, tliiu, reddish- 

 horny ; spire ratiier concave ; suture deep ; whorls 

 four, narrow, convex, closely radiately plicated, last 

 whorl but one prominent, the last not descending, a 

 little compressed from the side, very convex beneath ; 

 umbilicus broad, deep, rather angled at the edge ; 

 aperture vertical, rotundately lunar, higher than 

 broad ; lip simple, straight, margins rather approxi- 

 mating, joined by a very thin callosity. 



Benson, Ann. and Mag. Nat. Hist. 1S50, vol. v. p. 216. 



Hab. Cape of Good Hope (under stones near Green Point, 

 and on Camp-Ground) ; Benson. 



An interesting delicate Platwrbis -like species, broadly 

 openly umbilicatcd. 



Species 1182. (Mus. Benson.) 



IIklix cygnea. Hel. testa late ampUter umbilicatd, orbi- 

 culato-depresM, suhdiicoided, lemii, fusco-corned, undl- 

 ijue eximie aunulato-costellatd, striis spiralibus in in- 

 terstitiis sub lente minulimme decusiatd ; spird con- 

 vexd ; nuturd subcanuUculald ; anfractibns quatuor, 

 convexis, siibant/ustis ; aperlurd subcirculari ; peristo- 

 mate iimpUci, niarginibus conuiveniibus, columellari 

 breviter rejlexo. 



TuK SWAN Helix. Shell broadly largely umbilicated, 

 orbicularly-depressed, subdiscoid, thin, brown-horny, 

 delicately finely ring-ribbed tiiroughout, decussated 

 beneath the lens in the interstices with very minute 

 -tpiral striic; spire convex; suture sliglitly cliannelled ; 

 whorls four, convex, rather narrow ; aperture nearly 

 circular ; lip simple, margins approximating, colu- 

 niullar margin shortly reflected. 



UnNsitN, Ann. and Mag. Nat. Hist. 1853, vol. xi. p. 30. 



Ilftb. Perth, West Australia ; Dr. Bacon. 



A light horny species, delicately encircled throughout 

 with fine ring-like riblets. 



Species 11 S3. (Mus. Benson.) 



Helix rauiplicaTA. Ihl. iestd umbilicatd, depreud, 

 tenui, corned, plicis arcuatis »ul>diitantibui jHunild ; 

 spird pariim elevald; suturd profunda; anfraelibuM 

 quatuor, convexis, ultimo tereti, non deacendente ; umbi- 

 lico anyusto, pernio ; aperlurd parum obliqud, lunato- 

 circulari ; peristomate timplici, recto, mar/fiitibui con- 

 niventibus. 



The few-plaited Helix. Shell umbilicatcd, depressed, 

 thin, homy, furnished with rather distant arched 

 plaits ; spire but little raised ; suture deep ; whorls 

 four, convex, the last tapering, not descending ; um- 

 bilicus narrow, open ; aperture a little oblique, lunar- 

 circular; lip simple, straight, with the margins ap- 

 proximating. 



Benson, Ann. and Mag. Nat. Hist. 1S50, vol. vi. p. 254. 



Hab. Cape of Good Hope (under stones at Ga-cn Point) ; 

 Benson. 

 Allied to the preceding species, but more faintly and 



irregularly ring-sculptured. 



Species 11 S4. (JIus. Benson.) 

 Helix bidenticulata. Hel. testa umbilicatd, depretso- 

 conicd, obsolete radiato-striatd, albidd (decorticata) ; 

 spird subconicd, apice obtuso ; suturd ivipressd ; an- 

 fraclibus sex, crcte convolutis, convexis, omnibus su- 

 penie lineis (BquidistantUjus elevatiusculis instruetia, 

 ultimo carinato, subtus convexo ; aperlurd arete securi- 

 formi, verticali ; peristomate mnrtjiue superiore brevis- 

 simo, columellari oblique descendente, expansu, supemi 

 rejlexo, basali arcualo, dentibus minutis, distantibus, 

 submarginaUbus, dextro prominentiore, munito ; umbi- 

 lico pernio. 

 T(iE Two-TOOTiiED ITelix. Shell umbilicatcd, (Iiiuvjmn 

 conic, obsolctely radiately striated, whitish (decorti- 

 cated) ; spire subconic, obtuse at the apex ; suluit 

 impressed ; whorls six, closely convoluted, convex, 

 all furnished at the upper part with two equidistant 

 raised lines, last whorl keeled, convex beneath ; aper- 

 ture closely wedge-shaped, vertical ; lip with the 

 upper margin very short, the columcllar obliquely 

 descending, expanded, retlectcd above, the basal 

 arched, furnished with two miuute distant subaiar- 

 giiml teeth, of which the right is the more prominent ; 

 umbilicus open. 

 Benson, Ann. and Mag. Nat. Hist. 1852, vol. ix. p. 405. 

 Ilab. Nilgherry Mountains, south of India ; Jcrdon. 



.\ small trochiforra species, encircled with two vcrj' cha- 

 racteristic raised spiral lines, aud furnished with two small 

 teeth in the mouth. 



