134 CRETACEOUS LAMELLIBRANCHIA. 



Remarks. — C. obtusa, of which I have seen two specimens only, closely re- 

 sembles some forms of G. Saussuri, but differs in having narrower and less curved 

 umbones. It also resembles the more elongate forms of G. Sedgiviclci. 



Type. — In the Sedgwick Museum. 



Distribution. — Lower Greensand of Upware. 



CyrniNA cuneata, Sowerby, 1836. Plate XX, figs. 7-12. 



1836. Cypeina cuneata, J. de C. Sowerby. Trans. Ceol. Soc, ser. 2, vol. iv, pp. 



240, 341, pi. xvi, fig. 19. 



1849. triangularis, T. Brown. Foss. Conch., p. 207, pi. lxxxv, fig. 2. 



1850. cuneata, A. oVOrbigny. Prodr. de Pal., vol. ii, p. 161. 

 1854. J. Morris. Cat. Brit. Foss., ed. 2, p. 199. 



1865. F. J. Pictet and G. Campiche. Foss. Terr. Cn't. Ste. 



Croix (Mater. Pal. 



Suisse, ser. 4) p. 



230. 

 1870. F. StoliczJca. Palseont. Indica, Cret. Fauna S. India, 



vol. iii, p. 193 [Anisocardia (Veniel-la)']- 



Description. — Shell of small or moderate size, triangular, convex with flattened 

 sides, carinate, considerably inequilateral. Lunular margin long, concave. Anterior 

 margin regularly rounded. Ventral margin only slightly curved, sometimes 

 with the posterior part concave. Posterior margin short, truncated, almost 

 straight, nearly parallel to the height of the shell, forming a right angle with 

 the ventral margin and an obtuse angle with the long postero-dorsal margin. 

 Umbones prominent, high, curved considerably inward and forward. A distinct, but 

 rounded, carina extends in a gentle curve from the umbo to the postero-ventral 

 angle. In front of the carina the shell is sometimes slightly concave. Postero- 

 dorsal area narrow, sloping steeply except near the posterior margin. Lunular 

 region deep, indistinctly limited. Escutcheon elongate, bounded by a small carina. 

 Ornamentation consists of very fine growth-lines at regular intervals. 



Measurements : 



(4) (5) (6) 



31 29 26-5 

 2G 24 20-5 

 (1—10) Blackdown. 



Affinities. — The differences between G. Saussuri and this species are given 

 above (p. 132). 



The form from the Meule de Braequegnies which was referred to G. angulata, 





(i) 



(2) 



(3) 



Length 



, 48 



3G 



35 



Height 



. 40 



29 



29 



(7) 



(8) 



(9) 



(10) 



26 



20 



23 



20 mm 



21 



19-5 



20 



16 „ 



