132 EOCENE MOLLUSCA. 
The French specimens of the Cyprea tuberculosa are smaller and less triangular in 
form than our English shells; and the flattened posterior extremity is circumscribed 
by two lateral callosities which rise, one on each side, towards the back. This 
singular character, which forms a prominent feature in the specimen figured by 
M. Deshayes, and which I am assured by that gentleman is constant in the French 
shells, is wanting in the very few English specimens I have seen. Notwithstanding 
these differences, the English shells present such close affinities to the French 
specimens, that they must be regarded rather as a strongly marked local variety than 
as a distinct species. The dorsal tubercles, from which the specific name is taken, are 
stated by Mr. Sowerby not to be a constant character; they certainly appear to vary 
much in size and position, for in the figure and description given by M. Deshayes 
they are represented as of considerable size, andas ranged longitudinally about the 
middle of the shell; while in Duclos’s original figure, they appear to be much 
smaller, and are placed transversely near the posterior extremity. The English 
specimen now figured, presents an even surface ; but one, formerly in Mr. Bowerbank’s 
museum, and which, unfortunately, has fallen to pieces, had a single large tubercle 
near the middle. 
With regard to the genus to which this singular shell should be referred, a difference 
of opinion exists. The absence, or nearly obsolete condition, of the columellar teeth 
would seem to require that it should be placed, as in fact all the French authors have 
placed it, among the Ovule ; but the pyriform shape, the aperture, and the general aspect 
of the shell belong rather to Cyprea. Dr. Gray has pointed out the analogy between 
it and the tuberculated variety of the recent C. mus, and asserting in fact, that 
M. Deshayes’s specimen has a very few obscure teeth on the lips, he has stated that, in 
his opinion, the shell is evidently a cowry, an opinion from which Mr. George Sowerby 
has not dissented. On this authority, I have retained the shell in the present genus, 
of which, as Mr. James Sowerby has suggested, it may form with C. mus, a sub-genus. 
Size.— Axis, 6 inches and 6-10ths; diameter, 5 inches. 
Localities—Bracklesham Bay, where it is rare. irench: Rétheuil, Cuise-Lamotte, 
Pierrefonds, (Oise), (fide D’Orb). 
Section—TRIVIA. 
No. 76. Cypr#a PLatystoMaA. Ff. #. Edwards. Tab. XVII, fig. 7a—/. 
C. testd parva, ovato-oblongd, ventricosd, antice attenuata, transversim lineata, apice 
elevato ; lineis angulosis, numerosis, regularibus, sulco dorsal perspicuo, mediano, interruptis ; 
spatiis inter lineas concavis ; aperturd latd, postice sub-productd, flexuosa, canaliculatd, 
anticé brevi latoque canali exeunti, vix emarginatd ; labro extius late marginato, in medio 
leviter arcuato. 
Shell small, ovately oblong, ventricose, attenuated in front, almost pyriform ; trans- 
