TURBONILLID. IBIS 
Distr.—50 sp. World-wide. Range from low-water to 
90 fathoms. Fossil. Cretaceous—. T. elegantissima, Mont. 
(Ixviii, 98). 
Shell slender, elongated, many-whorled ; whorls plaited ; apex 
sinistral; aperture simple, ovate; peristome incomplete, colu- 
mella not plaited. Operculum horny, subspiral. 
Animal. Head very short, furnished with a long, retractile pro- 
boscis; tentacles triangular; eyes immersed at the inner angles 
of the tentacles; foot truncated in front, with a distinct mentum, 
operculigerous lobe with a minute conical appendage on each side. 
Comprises a great number of small, graceful white shells which 
have been grouped in a number of genera or subgenera. 
MorMuLA, A. Ad. Subulately-turreted, rissoid, solid, thick, 
longitudinally plicate; aperture large, columella spirally tortuous, 
lip thickened within, margin acute. A few Japanese species. 
T. rissoina, A. Ad. 
DUNKERIA, Carpenter, 1857. (In honor of W. Dunker, a dis- 
tinguished German conchologist.) Whorls rounded, cancellated. 
Numerous species. Mazatlan, Japan. T. paucilirata, Carp. 
Mazatlan. 
vanestA, A. Ad., 1861. Proposed for two species resembling 
Melania in external characters, but true marine shells, decussated 
by longitudinal and spiral ridges. 7. trifasciata,Sowb. China. 
SPIROCLIMAX, Moreh. Subcylindrical, pellucid, suture con- 
tabulate, aperture ear-shaped, lip thickened, sigmoidal, sub- 
marginate, inflexed at the suture. 1 sp. West Indies. 
MIROBELI<cUS, Sandb. 7. inaspecta, Fuchs. 
Strrepracis, Meek, 1871. 
Distr.—S. Whitfieldi, Meek. Carb.; Ills. 
Shell small, turreted, smooth; embryonal whorls planorbiform ; 
mouth oval. 
Ho.openia, M’Coy, 1852. 
EHtym.—olos, entire, and ope, an aperture. 
Distr.—Fossil, 12 sp. Silurian, Trias; Europe, United States. 
H. gregaria, Sowb. 
Shell elongated, slender, of numerous gradually increasing 
whorls, generally crossed by slightly arched strie; mouth cir- 
cular, with the peristome entire; base rounded, with or without 
a minute umbilicus. 
The shells of the species. composing this genus differ from 
those of Turritella in the continuous peristome and definite 
round margin to the aperture, thus approaching much nearer to 
Scalaria. 
EULImMeELLA, Forbes, 
Distr.—Eur., Japan. LF. Scille, Scacchi (Ixviii, 1, 2). 
Shell elongated, turriculate, solid, smooth, polished, whorls 
