i:)2 CRETACEOUS LAMELLIBRANCHTA. 



Drscrijdinn. — Slu'll convex, oval, longer than high. Antero-dorsal margin 

 short. Anterioi- margin produced, somewhat pointed, rounded, curving rapidly- to 

 join the slightly convex ventral margin. Posterior margin short, somewhat 

 truncated. Postero-dorsal margin long, convex, with a considerable ventral slope. 

 Umbo prominent, recurved. Lunnlar region deep. A faint carina extends from 

 the imibo to the jiostero-ventral extremity. Ornamentation consists of growth- 

 lines. Length 78 mm. Height 70 mm. 



Bemnrlcs. — The type, a right valve, now in the British Museum, is the only 

 undoubted example of this species which I have seen. From the nature of the 

 matrix there seems no doubt that this specimen comes from ihc vniiiimilatitm zone. 

 The hinge cannot he made out satisfactorily, l^ut the form of the shell agrees 

 closely with that typical of hocardia. 



Disfriliiition. — Lower Greensand (zone of BmiriUncoras mammihitnm) near 

 Sandu'ate.' 



i^ar»%— LUCINIDiE, Fleming. 

 Genus — Lucina, J. G. Brvtjuiere, 1797. 



(' Encyc. Metli., Vers,' pi. odxxxiv. Lamarck, ' Mi'm, Soo. Hist.. Nat. Paris,' 1799, p. 84.) 



LuciNA, sp. Plate XXIV, figs. 2, 3. 



Internal casts of a Lucina have been obtained from the Spilsby Sandstone 

 (/.one of Bdemnitcs latomli.^) of Donnington and Claxl)y. A right valve with the 

 shell preserved was found by Mr. Lamplugh in the Spilsby Sandstone at ITolton 

 and ])robably belongs to the same sjiecies as the casts. The shell bears numerous 

 small concentric ridges. 



Lucina, sp. Plate XXIV, figs. 4, 5. 



Some internal casts and a portion nf an external cast of Luciiin have been 



1 honiriVia f omnia, Forbes, 'Quart. Journ. Geol. Soc.,' vol. i (1845), p. 242, pi. ii, fig. 10, is 

 Known only liy Ibe imperfect typo specimen which is now iu the Museum of the Geoloi^ncal Society 

 (No. 21.')0), ami was obtaine.1 from the Lower Greensand of Alborfiolil. It was roforrod to Ojiix by 

 •rOrbigny, ' Prodr. de Pal.,' vol. ii (1850), p. 118. 



I.-dt-anlia cryptocoraa, d'Orbii^ny, has Itcon recorded by BaiTois from the Upper (Jroousand way 

 Devizes, Sec 'Terrain Cn't. suix'r. dc l"Anglelerrc ct .Ic I'lrlande' (187(')). p. 61. 



