159^ 



band, the last two pale bauds ; aperture circular, dark purplish- 

 black within ; peritremc brownish orange-coloured, rather thick- 

 ened, reflected, slightly spreading posteriorly, and somewhat 

 revolute over the umbilicus, which is small ; operculum externally 

 testaceous, internally horny, of few volutions. 

 Madagascar. Mus. Cuming. 



180. Cyclostoma zonulatum (Tab, Suppl. xxxi. a, f. 296, 

 297), Fermsac, MS. 



C. testa globoso-conica, albicante, fusco-zonulata ; spira levato- 

 conica, acuminata, apice obtusiusculo ; anfractibus quinque, 

 rotundatis, postice carinis quatuor ad quinque tenuibus, antice 

 striis vahdis instructis ; sutuifi distiucta; apertura circulari, peri- 

 tremate lato, albo, extiis expanso, intiis supra umbilicum postice 

 revoluto, antice angustato; umbilico parvo, striis nonnullis vahdis 

 instructo ; operculo testaceo, paucispirali. 



Shell globose-conical, whitish, girdled anteriorly with narrow 

 fuscous zones ; spire elevated, conical, acuminated ; its apex 

 rather obtuse ; volutions five, rounded, posteriorly with from foui' 

 to five slender keels, and anteriorly with well-marked stria ; 

 suture distinct ; aperture circular ; peritreme wlute, broad, spread- 

 ing outwards, and posteriorly revolute over the umbilicus on the 

 columellar side ; umbihcus small, spirally grooved witliin ; oper- 

 culum testaceous, of few volutions, wliite. 



Miis. Cuming. 



181. Cyclostoma laxatum (Tab. Suppl. xxxi. a, f. 302), 

 nobis. 



C. testa orbiculari-depressa, albida, epidermide aurantiaco- 

 brunnea induta ; spira depressa, apice rufescente ; anfractibus 

 quatuor, rotundatis, rugulosis, ultimo zonis duabus, altera albida, 

 altera fusca, striis incrementi validis; apertura subdepresso-cir- 

 culari, postice prope ultimum anfractum paulisper angulata; 

 peritremate tenui, antice paululiim reflexo ; umbihco maximo, 

 anfractibus quatuor conspicuis. 



Shell of a depressed orbicular form, whitish, covered with a 

 thick orange-brown epidermis ; spire depressed, with a rufous 

 apex; volutions four, rounded, covered not only with distinct 

 lines of growth, but also with irregular rugulosities, \ni\\ two 

 narrow zones, the posterior white, the other fuscous, in front of 

 wliich the epidermis is more darkly coloured ; aperture not quite 

 circular, but very shghtly elliptical, and with a slight angle pos 



