L96 CRETACEOUS LAMELLIBRANCHIA. 



1850. Cardium spHjEROideum, F. J. Pictet arid E. Benevier. Foss. Terr. Aptien 



(Mater. Pal. Suisse, ser. 1), 

 p. 77, pi. ix, fig. 3. 

 1866. F. J. Pictet and G. Campiche. Foss. Terr. Cret. 



Ste. Croix (Mater. Pal. Suisse, 

 ser. 4), p. 2(50. 

 1871. (? L^vicardium), F. Stoliczlca. Palseont. Iudiea, 



Cret. Fauna S. India, 

 vol. iii, p. 213. 



Description. — Shell stout, large, much inflated, higher than long, slightly 

 inequilateral. Anterior and ventral margins rounded. Posterior margins trun- 

 cated, forming angles with the postero-dorsal and ventral margins. Umbones 

 prominent, with a small forward curvature, and an inconspicuous carina extending 

 to the postero-ventral angle and limiting the flattened postero-dorsal area. 



Ornamentation consists of regular, broad, flat, concentric ribs separated by 

 narrow grooves. On the posterior area strong growth-ridges are present. 



Measurements : 



(1) (2) (3) (4) (5) 



Length . 79 76 . 73 69 . 47 mm. 



Height . 84 . 91 . 87 . 87 . 48 „ 



(1—5) Pema-hed, Isle of Wight. 



Affinities. — Pictet and Campiche state that this species is very near to 

 0. imbricatarium (Deshayes), 1 but that the posterior area is more flattened and 

 forms an angle with the sides of the shell ; also the truncated posterior margin is 

 relatively longer. 



Remarks. — In this species the radial ornamentation of the posterior area is 

 either very indistinct or quite obsolete. There is considerable variation in relative 

 height and length of the shell. 



Type. — From the Lower Greensand (Pe/nui-hed) of Sandown ; in the Museum 

 of the Geological Society. 



Distribution. — Lower Greensand (Perna-bed) of Atherfield and Sandown. 

 Recorded by Topley from the Hythe Beds of Hythe. 



Protocardia, sp. Plate XXXI, fig. 4. 



The collection of Upper Greensand fossils made by the late W. Vicary, which 

 is now in the British Museum, contains two imperfect right valves (No. L 17041) 



1 D'Orbigny, ' Pal. Franc. Terr. Cret.' (1844), vol. iii, p. 18, pi. ccxxxix, figs. 4 — 6; Leyrnerie, 

 'Mem. Soc. geol. de France,' ser. 2, vol. v (1842), p. 4, pi. v, fig. 2; Pictet and Campiche, 'Terr. 

 Cret. Ste. Croix' ('Mater. Pal. Suisse,' ser. 4, 1866), p. 258, pi. cxxi, figs. 6, 7. The specimens referred 

 to C. imbricatarium by Forbes are examples of Unicardium vectense (p. 163) ; see Forbes, ' Quart. 

 Journ. Geol. Soc.,' vol. i (1845), p. 243. 



