162 EOCENE MOLLUSCA. 



No. 100. Voluta denudata. Sowerby. Tab. XXI, figs. 5 a — c. 



Voluta denudata. Sow. 1840. Min. Con., vol. 7, p. 6 ; t. 93, fig. 3. 

 — — — 1850. Dixon's Geol. Suss., p. 120; t. 15, fig. /. 



V. testa ovato-oblongd, postice Icevi, antice transversim sulcata, profunde emarginatd ; 

 s])ird conicd, brevi, apice acuto ; costis brevibus, crassis, ad extremitates posterior es nodi- 

 geris ; anfractu ultimo superne concamerato : aperturd elongato-ovali, postice angustd ; labro 

 simplici, intus Icevi ; labio expanso, incrassato ; columella tri-plicatd. 



Shell oblong-ovate, ribbed, smooth, except towards the base, where it is transversely 

 furrowed ; spire short, conical ; apex small, pointed ; ribs thick, short, scarcely extend- 

 ing to the middle of the whorl, and terminating posteriorly in coarse, nodiform tubercles; 

 whorls rather ventricose in front, obtusely angulated at the shoulders ; the space 

 between the tubercles and the suture convex, imparting a dome-like shape to the lower 

 part of the spire. The aperture is of a lengthened oval form, narrow, obscurely chan- 

 nelled behind, widely and deeply notched in front ; the outer lip simple, smooth within ; 

 inner lip much spread over the front of the body whorl, extending backwards far up 

 the spire, and thickened. The columella is flattened in front, and presents one thick, 

 prominent fold in front, and two or three smaller ones behind. In the young shell, the 

 whorls are crowned with three rows of small, nodiform spines, and the margins between 

 the front row and the suture are somewhat depressed. The two posterior rows, which 

 correspond with the front row, rise out of faint, elevated lines, which traverse the sutural 

 margin; as the shell is enlarged, these spines are lost, and the transverse lines become 

 stronger; the direction of the suture also becomes less decurrent, so that each succeeding 

 whorl envelops more of the preceding one, and the margin of the last, in fact, covers the 

 front row of spines upon the whorl next to it ; the margins also become convex, and 

 assume the dome-like shape characteristic of the later whorls. 



Size.-^- Axis, 3 inches, nearly ; diameter, 1 and 7-10ths of an inch, nearly. 



Localities. — Bognor, where it is very common, and {fide Sow.) Brentford. 



No. 101. Voluta spinosa. Linnceus. Tab. XXI, figs. 4 «, b. 



Lister. Hist. Conchyl., t. 1033, fig. 71 



Gualtieri. 1742. Index Test. Conch., t. 55, fig. E? 



Conus spinosus. Linn. 1758. Syst. Nat., 10th edit., p. 715, No. 271. 



Buccindm (sp.) Walch. 1764. Das Steinreich System., &c, t. 11, fig. 2 a. 



Stbombus spinosus. Linn. 1767. Syst. Nat., 12th edit., p. 1212. 



— — Favanne. 1780. D'Argen. Conchyl., 3d edit., t. 66, fig. I, 9. 

 _ — Schroter. 1783. Einleit. in die Conch., vol. 1, p. 443, No. 24. 



— — Gmel. 1788. Linn. Syst. Nat., 13th edit., p. 3518, No. 27. 



