160 EOCENE MOLLUSCA. 
pansis ; sulcis transversis distantibus, ad basin latis, profundis: aperturd postice sub-cana- 
liculatd, antice late emarginatd ; labro tenui, simplici; labio effuso, postice incrassato ; 
columella arcuatd, quater vel quinguies plicatd. 
Var? Puatyspina, fig. le. Testa tuberculis nodiformibus, crassis, lateraliter com- 
pressis, coronata. 
Shell ovately oblong, contracted at the base, obscurely ribbed, transversely fur- 
rowed, with a short, rather conical, and pointed spire: whorls angulated at the 
shoulder, and crowned with a single row of large, wide-spreading spines. The bases 
of the spines are prolonged into thick, obscure ribs, which do not extend beyond the 
middle of the whorls. In the young state, the ribs are numerous, and surmounted by 
two rows of small, sharp spines ; as the shell increases in size, the ribs become more 
distant, and the row of spines nearest to the suture disappears, and is replaced by a 
sharp, elevated ridge. The transverse furrows are distant, and broad and deep at 
the base. The aperture is contracted in front, obscurely channelled close to the suture, 
and widely, but not deeply, notched in front ; outer lip thin, sharp edged, and smooth 
within ; inner lip widely spread, thickened posteriorly, and extending backwards as far 
as the suture; columella flattened in front, curved, and furnished with four or five folds, 
of which the one in front is the largest. In the last whorls, the sutural margin is 
spread over the preceding whorl up to the spines, which, in some instances, are covered 
by it. 
In the specimen represented by fig. 16, tab. 5, in Mr. Dixon’s work, the outer lip 
is broken off, and the shell consequently presents the turbinate form which charac- 
terises V. spinosa (Lamk.) ; and this circumstance probably induced Mr. Sowerby to 
refer it to that species; from which, however, it is distinguished by the transverse 
furrows, and the arched and flattened columella. 
In the specimen (fig. 1 ¢) for which the variety platyspina was proposed by Mr. 
Sowerby, the spines on the last whorl are converted into large, thick, laterally-com- 
pressed, knob-like tubercles. The animal had, apparently, attained great age; and, as 
I am not aware of any similar specimen having been found, I am inclined to regard the 
individual in question as a monstrosity rather than as a variety. 
The present shells much resemble /. a///eta in the character of the spines, and in 
the conditions of the inner lip and the columellar folds; but the deep transverse fur- 
rows, which continue to be strongly marked even in adult specimens, entitle them, ap- 
parently, to specific distinction. 
Size.—Axis, ; diameter, 
Locality.—Bracklesham Bay. 
