ACHATINELLA.— Plate VI. 



any other of the genus, compomuled of Bidimus and 

 Jchatindla. With the generic callous twisted-plait co- 

 lumella of the latter genus, the shell is characterized by 

 the form, substance, and design of colouring of the former. 



Species 44. (Mus. Cuming.) 



AcHATlNELLA PLICATA. Achat, testd acminato-tnrritd, 

 gracili, teimiculd, sinistrorsd, anfractibus sex, coimexis, 

 carinis spiraliius numerom acutu undique sculptis, 

 suturis suhexcavatis, columella callosd, plied obsoletd, 

 aperturd parvd, labro simplici ; fuscescente-albd, ad 

 apiceiii obscure fidyuratd. 



The plicate Achatinella. Shell acuminately turreted, 

 slender, rather thin, sinistral, whorls six in number, 

 convex, sculptured throughout with numerous sharp 

 spiral keels, sutures rather excavated, columella cal- 

 lous, plait obsolete, apertm-e small, lip simple ; 

 brownish-white, obscurely waved at the apex. 



MiGHELS, MS. Pfeiffer, Mon. Helic. viv. vol. ii. p. 23.5. 



Hab. Moko Kai, Sandwich Islands. 



This also is of a difl'erent type from any of the pre- 



ceding species, and one of very abnormal character. It is 

 the only form that presents any external raised sculpture, 

 and the plicate columella by which the genus is chiefly 

 characterized is almost obsolete. 



Species 45. (Mus. Cuming.) 



Achatinella bacca. Achat, testa abbreviato-conicd, 

 dextrorsd, subventricosd, anfractibus eonvexis, superne 

 marginatis, columelld plicato-contortd ; intense nigri- 

 cante-castaned, suturis flavidis, columelld pallid ro- 

 saced. 



The BEiiEY Achatinella. Shell abbreviately conical, 

 dextral, rather ventricose, whorls convex, margined 

 round the upper part, columella plicately twisted ; 

 very dark chestnut, sutures yellowish, columella 

 pinkish. 



Hab. ? 



The shell here described does not appear to have 

 reached maturity, but, allowing for this, it is still charac- 

 terized by a much wider and shorter plan of convolution 

 than any of the species which have preceded it. 



