CYCLOSTOMA.—Prars VI. 
Species 31. (Fig. a, 6, Mus. Cuming.) 
CYCLOSTOMA FORMOSUM. 
vato-umbilicatd, depresso-turbinata, fumeo-grised, ma- 
culis parvis fulvis et albis ad carinas et suturas arti- 
culatd, spird elevatiusculd, anfractibus undique de- 
cussatim striatis, superné declivi-planis, deinde acute 
remote tricarinatis carinis duabus superioribus lami- 
nato-acutis ; apertura subcirculari, fauce purpureo- 
fusca, labro subreflexo, albo, interdum sanguineo. 
THE BEAUTIFUL CycLostoma. Shell very openly exca- 
vately umbilicated, depressly turbinated, smoky-grey, 
articulated at the keels and sutures with small ful- 
vous and white spots; spire somewhat raised, whorls 
everywhere decussately striated, slopingly flattened 
round the upper part, then sharply distantly three- 
keeled, the two upper keels laminately acute ; aperture 
nearly circular, interior purple-brown, lip moderately 
reflected, white, sometimes blood-stained. 
Sowersy, Pro. Zool. Soc. 1849, p. 15. pl. 2. f. 8, 9. 
Hab. Madagascar. 
Cycl. testd patentissime eaca- 
This truly beautiful shell is formed on the type of the 
old C. carinatum, but it is a very distinct species. 
Species 32. (Fig. a, 6, Mus. Cuming.) 
CycLostoMA castuM. Cycl. testd subprofundé umbilicati, 
globoso-turbinatd, tenui, semipellucido-albd, ad peri- 
pheriam fuscescente obscuré fasciatd, anfractibus ro- 
tundatis, undique dense spiraliter tenuiliratis, inter- 
stitiis striis subtilibus obliquis minute decussatis ; 
apertura circulari, labro tenue expanso. 
Tae cHastp CycLtostoma. Shell rather deeply umbi- 
licated, globosely turbinated, thin, semitransparent- 
white, obscurely banded with pale brown at the peri- 
phery, whorls rounded everywhere, densely finely 
ridged, interstices minutely decussated with fine ob- 
lique strize; aperture circular, lip thinly expanded. 
Preirrer, Pro. Zool. Soc. 1854, p. 150. 
Hab. Madagascar. 
Resembling C. asperum in general appearance, but more 
densely and finely sculptured, while the whorls are more 
loosely openly convoluted. 
Species 83. (Mus. Cuming.) 
CycLostomMa mMopustuM. Cyel. testa latissime patente 
umbilicatd, depressd, subdiscoided, fuscescente-albd, 
spira plana, anfractibus angustis, ad suturas impressis, 
deinde rotundatis, undique spiraliter liratis et striatis, 
liris subdistantibus, striis transversis scabrosis dense 
decussatis ; apertura oblique circulari, pared, labro 
antice fimbriato. 
THE mMopEsT CycLostoma. Shell very broadly openly 
umbilicated, depressed, nearly discoid, brownish- 
white; spire flat, whorls narrow, impressed at the 
sutures, then rounded, everywhere spirally ridged and 
striated, the ridges being rather distant, densely de- 
cussated with transverse scabrous strie; aperture 
obliquely circular, small, lip frilled in front. 
Perit, Journ. Conch. 1850, p. 50. pl. 4. f. 2. 
Hab. Island of Abd-el-Goury ; Petit. 
This species is convoluted on the same plan as the little 
thread-encircled C. diratum, but the sculpture is much 
more densely and strongly developed. 
