128 | EOCENE MOLLUSCA. 
No. 71*. Cypr@A OvIFORMIs. Sowerby. Tab. XVI, f. la—z. 
Cypr™a ovirormis, Sow. 1812. Min. Con., vol. i, p. 17, t. 4, 3 lower fig. 
= — Defr. 1826. Dict. des Sci. nat., vol. xlii, p. 40. 
OVULUM RETUSUM, Sow. 1834. (Wetherellon Hampstead Heath Well,) Geol. Trans., 2d. Series, 
vol. v, p. 136, t. 8, fig. 19. 
Non Cyprma ovirormis, Galeotti. 1837. Mém. surla const. géog. &c. de Brab., p, 183, No. 12. 
C. testdé sub-globosd, unticé attenuatd, levi: apertura posticé elongata, flexuosa, angus- 
tissimd, antice latiori, extremitatibus canaliculatd, ad basin emarginatd ; labro postice et in 
medio compresso et incrassato, anticé acuto, expanso, extus marginato, intus regulariter 
dentato ; labio antice compresso, in callum fastigiosum ad basin tendentem lateraliter 
expanso ; columella planulatd, anticé concavd, dentato-plicatd. 
Shell sub-globose, narrowing gently towards the base, where it is produced into a 
short wide beak or canal, slightly notched in front, smooth: aperture elongated, curved, 
very narrow, but expanding a little before it enters the anterior canal; the outer lip 
prolonged at the posterior extremity, thickened ; compressed until nearly opposite the 
wide part of the aperture, where it becomes thin and elevated, and is flattened on the 
inner surface ; a narrow raised border, more or less prominent in different individuals, 
runs along the outer margin, and joins the thin elevated part of the lip. The teeth 
are numerous, short, not extending beyond the inner margin, and almost obsolete on 
the anterior part of the lip. The inner lip, towards the front, expands into a narrow 
ridge-like prominence, which extends to the very base; and at the posterior extremity 
rises into an angular callus, forming the left wall of the posterior canal. The columella 
is flattened, hollowed towards the front, and covered with numerous slender pliciform 
teeth. 
The projecting margins, imparting to the front of the aperture the resemblance of a 
wide trough, form a character by no means common among the Cypree ; it is found, 
although not so prominently, in @. everta (Desh.), a species from the sadles infé- 
riewrs of the Paris Basin, and in the English C. Barfonensis. A short and very globose 
variety (fig. 1¢) occurs at Whetstone, in which the projecting margins are farther 
apart, and the trough, consequently, is wider than in the type. The specimen figured, 
which is from Mr. Wetherell’s collection, has lost part of the anterior canal. 
In the young state, this Cypreea is almost pyriform, being much more produced and 
attenuated in front; and it is covered with very numerous transverse raised lines, 
traversed by sharp, perspicuous lines of growth; the aperture is much lengthened and 
curved at the posterior extremity, wide, and-very effuse in front, and the columella is 
twisted. In this state it has the appearance of an Ovula, and, in fact, an immature 
individual of the species obtained by Mr. Wetherell, from the well sunk at the Lower 
Heath, Hampstead, has been described by Mr. Sowerby as Ovulum retusum. A selection 
from the beautiful series of specimens in Mr. Wetherell’s cabinet, with the aid of some 
