TURBINID. 307 
TURBONITELLA, de Koninck, 1881. 
Distr.—Devon. to Carb.; Europe. T°. biserialis, de Kon. 
Shell turbiniform, with convex, smooth or nodulous whorls ; 
mouth round or oyal,inner lip callously thickened, outer lip 
sharp, thin; a narrow umbilical slit. 
RHABDOPLEURA, de Koninck. 
Distr.—Monodonta solida, Kon. Carb. 
Conieal, height and diameter about equal; whorls 4—5, slightly 
convex, rapidly enlarging, the last more than half the total 
length, striate, and finely spirally ribbed; aperture transversely 
rounded; inner lip somewhat callous,curved and thickened below. 
OnxospPirRA, Zittel. 
Distr.—O. ranellatus, Quenst. Coral Rag. 
Shell thin, lengthened-trochiform, spire pointed ; whorls con- 
vex, spirally ribbed, keeled or clathrate with one or two varices, 
which are continuous, as in Ranella; mouth rounded-ovate ; 
columella forming an angle with the thickened outer lip. 
Hamusina, Gemmellaro. 
Distr.—Lias; Europe. H. Bertheloti, d’Orb. 
Shell thin, conical-turreted, sinistral, tuberculate, imperforate ; 
spire sharp; body-whorl angular; aperture rounded, inner lip 
callous. 
PLatTyAckA, v. Ammon, 1882. 
Distr.—Rheetian ; Bavaria. P. impressa, Schafh. 
Shell thin, turreted, sinistral, widely and deeply umbilicate ; 
whorls with a nodulous keel; apex flattened. 
ImMpERATOR, Montfort. 
Syn.—Astralium, Link. Bomeateiees Swn. Canthorbis, Swn. 
Hercoles, Montf. 
Distr.—50 sp. East and West Indies, W. Gaon, Australia. 
Fossil. Trias—. 
Shell trochiform, depressed conic; whorls rugose or spinous, 
the latter especially at the sharply angulated periphery of the 
last whorl; aperture subquadrangular, subtruncated in front. 
Operculum calcareous. 
IMPERATOR (restricted). Umbilicated. Operculum with a 
subcentral tubercle and a spiral submarginal rib. J. longispina, 
Lam. (Ixxx, 23, 24). 
cALCAR, Mont. (Stella, Klein. Cyclocantha, Swains. Astrea, 
Bolt. Turboidea, Seeley.) Not umbilicated; spire more ele- 
vated. Operculum externally subspiral, and with a central pit. 
W. Indies, Indian Ocean. J. stellaris, Gmel. (1xxx, 25). 
GUILFORDIA, Gray. Periphery with long spines; whorls granouse, 
