310 EOCENE MOLLUSCA. 
The close resemblance which this Pleurotoma presents to P. granata, both in form 
and in ornamentation, would lead to its being regarded rather as a variety of, than 
as distinct from, that species; but the narrower and less concave margins, and the 
simple, rounded shoulders of the whorls, the more conical form of the spire and of 
the last whorl, and especially the deep, oblong sinus, distinguish it. 
Like P. rotundata and P. granata, this species presents a close analogy with 
certain shells from the lower Eocene deposits of Germany, figured, but not as yet 
described, by Beyrich (‘ Norddeutschen Tertitrgeb.,’ tab. xxix, fig. 2); but on the 
grounds before mentioned, it would be hasty to assume the identity of the English and 
German shells. 
' Stze-—Axis, 10-12ths of an inch; diameter, 4-12ths of an inch. 
Localities.—Highgate, Potter’s Bar. 
No. 236. Prteurotoma ta&viuscuta. fF. #. Edwards. Tab. XXXII; fig. 9, a, 6. 
P., testa elongato-fusiformi, sub-turritd, leviusculd: anfractibus convexiusculis; ad 
humeros in juventd tuberculatis, deinde simplicibus, postice et antice transversim lineatis, 
ceterum levibus ; marginibus posticis canaliculatis : aperturd oblongo-ovali, in canali angusto, 
brevi, exeunte ; labro leviter arcuato, tenui ; sinu lato, breviusculo, sub-trigono, ad humerum 
collocato. 
Shell elongated, fusiform, nearly smooth ; the spire, formed of six or seven volu- 
tions, is rather thick and pointed, and is nearly as long as the aperture. The whorls 
are slightly convex, and in the early stages of growth present on the shoulders a series 
of close-set, oblong tubercles, which become obliterated on the third or fourth whorl, 
after which the shoulders are smooth; the posterior margins are ornamented by three 
or four concentric, raised lines; of these the one nearest the suture is sharp and 
ridge-like, and more prominent than the others, and immediately in front of this the 
margin is traversed by a rather deep, narrow channel; the other marginal lines are 
feeble and somewhat obscure; the middle of the whorls is smooth; the front parts 
and base are covered with numerous, close-set, raised lines, rounded on the upper 
surface; these lines are irregular and unequal, fine lines alternating with thicker ones. 
The aperture is of an oblong-oval form, and terminates in front in a narrow, short, 
but distinct canal; the outer lip is thin, smooth within, and but slightly arched ; 
and the sinus, which is on the shoulder, is wide, not very deep, and somewhat three- 
cornered. 
The smooth surface of this Pleurotoma is not a common character, and entitles it 
to specific distinction. 
Size. —Axis, rather more than 7-12ths of an inch; diameter, 5-24ths of an inch. 
Locality.—Brockenhurst. 
