SUPPLEMENT TO THE BIVALVIA. 11 
CyrENA CUNEIFORMIS, Goldf. Petr. Germ., t. xi, p. 224, pl. 146, fig. 2, 1838. 
— tricona, fd. Idem., figs. 3, 4. 
_- suBaRaTA, Bronn. Leth. Geogn., t. xi, p. 958, pl. xxxviii, fig. 2, 1854. 
Spec. Char. C. Testd crassé, ovato-trigond vel cuneiformi, oblique cordatda, 
inequilaterali, postice angulatd, antice rotundatd, striatd, striis transversis imbricatis con- 
spicuis, posticé obsoletis, cardine bidentato, dentibus lateralibus levigatis. 
Dimensions. 13ths by 13th of an inch. 
Localities. Britain: Hempstead, Bembridge (J/orris). 
France: Sables supérieurs (Deshayes). 
Belgium: Klein Spauwen (/Vys¢). 
This is said by Mr. Morris (‘ Mem. Geol. Survey,’ 1856, p. 146) to be very abundant 
in Hempstead Cliff, and the specimens to be variable in form; but this variation appears 
to be principally in a more or less extension of the posterior side of the shell, some being 
more elongated than others. It resembles C. cvneiformis in outward form and in its 
variability, and is intermediate between it and what I have called strigosa, which is 
strongly and regularly ridged over all parts of the shell. The present species is not 
only distinguished from the two first mentioned by its exterior markings, but the hinge 
is narrower, with smaller denticles, the angular ridge on the posterior region is more 
strongly marked, and the lateral denticles are not striated. In well-preserved specimens 
there are, as Mr. Morris remarks, from five to seven radiating bands of colour upon the 
outer surface, such as may be seen on other species of this genus. 
14, Cyrmna Britannica, Desh. Tab. B, fig. 2 a, 6. 
Cycias DEPERDITA, J. Sow. Min. Con., tab. 162, fig. 1, 1817. 
CYRENA — Morris. Cat. Brit. Foss., 2nd edit., p. 200, 1854. 
—  Brirannica, Desh. An. sans Vert. du Bas. de Par.,t. i, p. 501, 1860. 
Locality. Charlton (J. Sowerby). 
1 have been unable to discover the specimen from which James Sowerby figured 
and described this species, or to learn of any other specimen having been found, and 
inasmuch as Mr. Sowerby speaks of it in ‘ Min. Con.’ as a common species at Charlton, 
I should have supposed that he was labouring under some mistake about it, were it not 
that his well-known accuracy of delineation precludes the idea of his not having had 
before him some shell of which his figure is a fairly correct representation ; and as this 
representation is obviously of some species of the genus Cyrena, and of one unlike any 
of the others known and described from English Eocene deposits, I have felt it necessary 
to have his figure copied into my plate, and to give the species among the British Eocene 
Cyrene. 
