PROSOBRANCHIATA. 291 
may be regarded as a variety. The shell, however, is wider, the spire more obtuse, 
and the body-whorl shorter and more contracted in front; these differences, 
joined to the peculiar transverse lineation and the smooth, untuberculated keel, have 
induced me to regard the species as distinct. 
Size—Axis, 10-12ths of an inch; diameter, 4-12ths of an inch nearly. 
Locality.—Stubbington. 
No. 215. Prevroroma cauuirera. JF. 2. Edwards. Tab. XXX, fig. 9, a, 4; fig. 10, 
CRANES ERLE Y OU 
P. testd sub-turrita, omnino concentrice lineatd: spird obtusiusculd: anfractibus 
depresso-conveais ; ad -humeros angulatis, fasciold tuberculatd sulcoque spirali bipartitd 
cinctis ; marginibus posticis concavis, ad suturam lined elevatd marginatis ; lineis concen- 
tricis supra medias partes anfractuum et canalem distantibus, irregularibus, per-elevatis, 
denticulatis ; supra humeros et margines posticas exilibus, confertis: aperturd ovali, in 
canalt breviusculo, obliquo exeunti; labro arcuato, ad humerum profunde sinuato, intis 
callos duos oblongos, alterum verticalem, alterum transversum, gerente ; sinu lato, triangulari. 
Var. RaPuivM (fig. 11, a, 6) ; testd minori, angustiori ; spird graciliori ; lineis concen- 
tricis sub-distantibus, regularibus, simplicibus. 
Var. MONILIGERA (fig. 10, a, 6) ; testd spird elatiort : anfractibus postice granulato- 
marginatis ; liners transversis medianis distantioribus, pre-denticulatis. 
Shell elongated, turreted, ornamented with concentric, raised lines; the spire 
somewhat obtuse and elevated, exceeding the aperture in length; the whorls, seven or 
eight, flatly convex and angulated at the shoulders, round which runs a narrow, 
elevated band, traversed along the middle by a deep furrow, and presenting a series 
of close-set, regular, vertical tubercles, divided by the transverse furrow, and separated 
by concave spaces as wide as the tubercles; the posterior margins, which slope 
gently backwards, are concave and bordered round the suture by an elevated, sharp- 
edged, ridge-like line; the last whorl is much contracted towards the middle, and 
terminates in front in a rather short, moderately wide, oblique canal. The concentric 
lines are irregular, prominent, and evenly and rather strongly granulated ; they are 
very fine and thread-like, close-set, regular, and simple, over the shoulders and pos- 
terior margins of the whorls; distant over the middle of the whorl, but more close 
over the canal. The aperture is ovate: and the outer lip, which is arched, thin, and 
sharp on the edge, presents within two oblong callosities ; of these one is narrow, ver- 
tical, curved, and distant from the edge, and it extends from the sinus to the canal ; 
the other is placed transversely, immediately over the posterior end of the vertical 
