158* 



lines and bands ; spire somewhat acuminated, whorls five to six, 

 rounded, smooth, the last ventricose, slightly carinated, carina 

 white ; aperture circular, chestnut-coloured within ; peritreme 

 pale orange- coloured, broad, spreading outwards, somewhat re- 

 flected over the umbilicus, which is rather large and spirally 

 grooved within. 



Our figure 125, which we have given as a variety of C. obso- 

 letum, should rather have been given as C. Madagascariense, var., 

 Gray, and the synonym under C. obsoletum should be omitted. 

 The operculum is testaceous and of few volutions. 



Madagascar. 



178. Cyclostoma Siamense (Tab. Suppl. xxxi. a, f. 292, 

 293), nobis. 



C. testa depresso-subglobosa, albida, strigis maculisque casta- 

 neis angulariter flexuosis picta ; spixa subdepresso-conica, subacu- 

 minata ; anfractibus 3i, rotundatis, ultimo maximo, ventricoso ; 

 sutura distincta, tenui ; apertura circulari, maxima, intus alba ; 

 peritremate incrassato, pallide aurantiaco, rotundato, reflexo ; um- 

 bilico majusculo. 



Shell of a somewhat depressed globose form, whitish with 

 angular markings and streaks of a chestnut-colour ; spire some- 

 what depressed, conical, slightly acuminated ; whorls 3^, rounded, 

 the last very large, ventricose, with a distinct linear suture; 

 aperture very large, circular, white within ; peritreme thickened, 

 of a pale orange-colour, rounded and reflected ; umbilicus rather 

 large. The entire surface of the shell is covered with very minute 

 granules, irregularly arranged in spiral rows. 



Siam. 



179. Cyclostoma xanthocheilus (Tab. Suppl. xxxi. a, f. 

 294, 295), nobis. 



C. testa conico-subglobosa, laevi, aurantiaco-brunnea, fusco 

 uni- vel bifasciata ; spira subelevato-conica, obtusiuscula ; anfrac- 

 tibus quinque, rotundatis, primis unifasciatis, ultimo pallide bifas- 

 ciato ; sutura distincta ; apertura circulari, intus purpureo-nigri- 

 cante ; peritremate aurantiaco, subincrassato, reflexo, postice 

 subexpanso, supra umbilicum revoluto ; umbibco parvo ; operculo 

 subtestaceo, paucispirali. 



Shell somewhat conical, globose, smooth, orange-brown, with 

 one or two fuscous spiral bands ; spire rather elevated, conical, 

 slightly obtuse ; volutions five, rounded, the posterior having one 



