38 CRETACEOUS LAMELLIBRANCHIA. 



Measurements : 





(i) 



(2) 



Length . 



35 



21 mm 



Height 



21 



. 17 „ 



Umbo to postero-ventral angle 



47 



• 26 „ 



(1) Perna-bed, Atnerfield. 



(2) Crackers, 



Atherfield. 



Affinities. — This differs from all other Cretaceous species with which I am 

 acquainted. The form of the shell and the character of its ornamentation agree 

 closely with the recent Scaphula, but since in our species the interior is unknown, 

 I refer it with considerable doubt to that sub-genus. 



Type. — In the Museum of the Geological Society (No. 2152), from Peasmarsh. 



Distribution. — Atherfield Beds of Sevenoaks, Peasmarsh, East Shalford, and 

 Redcliff (Isle of Wight). Crackers and Perna-bed of Atherfield. 



2. Upper and Lower Cretaceous Species. 

 Barbatia maeullensis (oVOrbigny), 1844. Plate VII, figs. 4, 5 a — d, 6 o, b, 7. 



1844. Akca maeullensis, A. d'Orbigny. Pal. Franc;. Terr. Cret., vol. iii, p. 205, 



pi. cccx, figs. 3 — 5. 



1854. — J. Morris. Cat. Brit. Toss., ed. 2, p. 185. 



1855. — G. Cotteau. Moll. Toss, de l'Yonne, p. 87. 



1866. — — F. J. Fictet and G. Campiche. Toss. Terr. Cret. de 



Ste. Croix (Mater. Pal. Suisse, ser. 4), pt. 3, 

 pp. 432, 468, pi. cxxx, figs. L— 4. 



1867. — — P. de Loriol. In A. Favre, Kecherch. geol. dans 



Savoie, &c, vol. i, p. 382. 



1869. — — F. de Loriol and V. Gillieron. Mon. pal. et strat. de 



l'etage Urgon. inf. du Landeron (Mem. Soc. 



Helvet. des Sci. Nat., vol. xxiii), p. 16, pi. i, fig. 13. 



1871. — -F. Stoliczka. Palseont. Indica, Cret. Fauna S. India, 



vol. iii, p. 342 {Barbatia). 

 1883. — — W. Keeping. Foss., &c, Neoc. Upware and Brickhill, 



p. 114. 



Non 1850. Bvssoakca marullensis, J. de C. Soicerhy. In F. Dixon, Geo]. Sussex, 



p. 355, pi. xxviii, fig. 11. 

 — 1878. — Sowerby. Ibid., ed. 2, p. 385, pi. xxviii, fig. 11. 



Description. — Shell oblong, inequilateral, rather compressed. Anterior and 

 posterior margins rounded, the postero-dorsal somewhat oblique ; ventral margin 

 parallel to the dorsal. Umbones not prominent, rather close ; carina near the 



