﻿6 



EOCENE MOLLUSCA. 



the siphonal or posterior side also is rather more distinct than in cuneiformis, and the 

 anterior lateral tooth is rather narrower and more elongated ; but the ornamented exterior 

 is the principal character that seems to justify its being placed in a separate specific 

 position. 



5. Cyrena Forbesii, Deshayes. Tab. A, fig. 5 a, b. 



Cyrena Forbesii, Desk. An. sans Vert, du Bas. de Par., t. i, p. 510, pi. xxxvii, 

 figs. 24—27, 1860. 



Spec Char. C. Testa ovato-lrigond, subtransversd, inaquilaterali, turgiduld, posterius 

 depressd, obtuse angulatd, transversim obsolete striata; umbonibus prominentibus obliquis ; 

 latere antico rotundato, postico acuminato ; cardine incsqualiter tridentato, dentibus divari- 

 catis ; dentibus lateralibus crassis incequalibus. 



Length, l^th of an inch ; height, 1 inch. 



Localities. Britain : Charlton. (S. Wood.) 

 France : Sainceny. 



This has been separated, and I think justly, by M. Deshayes from Cyrena antiqua, 

 Eerussac. Speaking of C. antiqua, however, M. Deshayes says ('An. sans Vert, du Bas. 

 de Par.,' torn. 1, p. 510) that "M. Hebert en a recueilli de nombreux echantillons dans 

 les environs de Dieppe ; elle est egalement en abondance dans les Lignites de Woolwich 

 en Angleterre." This statement is, I think, an error as far as Woolwich is concerned, 

 for I have not been able to see the true antiqua from our own beds. 



My researches in the Woolwich beds at Charlton were confined to a large excavation 

 that was open when I hunted it fifty years ago, and I have not since visited it. My 

 specimens have, however, ever since been carefully kept with the localities attached, and 

 I give them as undoubtedly genuine. 



6. Cyrena Dulwichiensis, Bichnan. Tab. A, fig. 14 a — c. 



Cyrena Dulwichiensis, Rickman. Quart. Jour. Geol. Soc, vol. xvii, p. 6, 1861. 



— ~ Edwards. Geologist, p. 210, pi. v, figs. 4, 5, 1860. 



— — J. Lowry. Chart. Brit. Tert. Foss., pi. iv, 1866. 



Spec. Char. C Testa oblongo-transversd, crassiusculd, incequilaterali, laevigata vet 

 obsolete striata umbonibus minimis depressis via; obliquis ; dentibus cardinalibus tribus, 

 lateralibus incequalibus, elongaiis, angustis, tenuissime striatis. 



