HELIX.— Plate CIX. 



mtd, ill/laid, sub-Trochiformi, teniti, pellucido-corneo- 

 iilSida, supemi lineU conceiitricis el oUirjuU creberrimi 

 dicMiatd, i/ifertie hniyalu, nilente ; ipird acuta ; an- 

 fractUms sex, coiiveriiucidis, ultimo carinato, liasi tit- 

 inUlo ; apertiird lunari ; perulomate simpUci, ad colit- 

 vieUam tenue dilatalo et rejlexo, umbiliaitii fere tegenle. 



Layakd's Helix. Shell scarcely uml)ilicate(l, conically 

 turbinated, intlatcd, somewhat Trorhus-shaped, thin, 

 transparent honiy-white, very closely decussateil on 

 the upper part with oblique and concentric lines, 

 smooth and shining upon the lower ; spire sharp ; 

 whorls six, rather convex, the last keeled, swollen at 

 the base ; aperture lunar ; lip simple, thinly dilated 

 and reflected at the columella, almost covering the 

 umbilicus. 



Pfeiffer, Pro. Zool. Soc. 1851. 



Hub. Ceylon; Layavd. 



A species of very characteristic form and sculpture, ex- 

 tremely thin and transparent. 



Species 615. (Fig. a, b, Mus. Cuming.) 



Helix Zoxites. Rel. (esfd umbilicatd, depressd, tenui, 

 diaphand, confertim costiilaio-striatd, lutescente-corHed, 

 fascia unicd aid pliiribus cadaneis, plerumque latitis- 

 culis, ornatd; anfractibus sex, sttperiw plaiimscidis, 

 ultimo ad peripheriam rotundato,basi laviore, iiiteule ; 

 umbilico parw ; aperturd oblique lunari ; peristomate 

 dmplici. 



The Zonites Helix. Shell umbilicated, depressed, thin, 

 diaphanous, closely rib-like striated, yellowish-horny, 

 ornamented with one or more chestnut bands, mostly 

 rather broad; whorls six, rather flat at the upper 



part, the Inst rounded at the periphery, smoother and 

 shining at the base ; umbilicus small ; aperture ob- 

 liquely-lunar ; lip simple. 



Pfeiffek, Pro. Zool. Soc. 1845, p. 127. 



Ilab. Vera Cruz. 



The specimen described by Dr. PfeifTcr was fncircliil 

 by only a single chestnut band next the suture; that lure 

 described and figured has three broad bands. 



Species 616. (Mus. Cuming.) 



Helix bectangixa. Ilet. testa imperforatd, orbiculalo- 

 conicd, solidd, striaiuld, griseo-stramined, fasciis Ititit 

 caslaneis ornatd, lined sulurali aredque basati cada- 

 neis ; spird el^atd, oblund ; anfractibus sex ad teplern, 

 cotivexiusculis, ultimo subrectanguH carinato, bati pta- 

 niuscnh, medio stibexcavato ; aperturd depressd, nib- 

 trape:id, margins columell/iri incrassato, calloso-snbiini- 

 dentato. 



The niGiiT-ANGLED Helix. Shell imperforated, orbi- 

 cularly conical, solid, finely striated, greyish stmw- 

 colour, ornamented with chestnut bands, sutural line 

 and basal area chestnut ; spire elevated, obtuse ; 

 whorls six to seven, rather convex, the last keeled at 

 a right angle, base rather llat, slightly excavateil in 

 the middle; aperture depressed, subtrapezoid, colu- 

 mellar margin thickened, with a slightly developed 

 callous tooth. 



Pfeiffer, Pro. Zool. Soc. 1845, p. 140. 



Ilab. Marquesas Islands. 



A solid Trochus-shaped shell of the form of an abrupt 

 cone. 



