CYPPJXA. 137 



Cypeina, sp. Plate XX, fig. 1 I. 



A few specimens of a small Cyprina, with the shell imperfectly preserved, 

 have been found in the Speeton Clay (D, 1). 



Cyprina anglica, sp. nov. Plate XX, figs. 15, 16. Plate XXI, fig. la, b. 



Description. — Shell of moderate size, oval, inflated, very inequilateral. Anterior 

 margin rounded, forming a continuous curve with the convex ventral margin. 

 Posterior margin less convex than the anterior, sometimes slightly truncated, more 

 or less oblique, usually curving gradually to join the ventral margin. Postero- 

 dorsal margin long, slightly convex. Antero-dorsal margin short, nearly straight. 

 Umbones broad, anterior, curving inward and forward. Postero-dorsal part of 

 shell slightly compressed ; carina absent or indistinct. Lunule ovate, depressed, 

 more or less distinctly limited. Ornamentation consists of growth-lines. 



Measurements .- 



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



Length 42 . 41 . ;J8 . 32 



Height 35 . 33 . 31 . 24 



Thickness 28 . 2&b . 24 . 16-5 . 



(1 — 0) Crackers, Atliorfield. 



Affinities. — C. anglica does not appear to be closely related to any other 

 English species. Externally it shows some resemblance to G. angulata, Sowerby 

 (see below), but is of much smaller size, more elongate, with a more or less 

 distinctly limited lunule, and either without a carina or with an indistinct carina 

 near the umbones. 



Remarks. — Nearly all the specimens show the two valves united, so that the 

 hinge and pallial line do not appear to have been seen by previous workers ; this 

 probably accounts for the fact that in several collections the species has been 

 referred to the genus Venus. A left valve, from which I have removed the matrix, 

 shows that the hinge agrees with Cyprina, and that there is no pallial sinus. 



Type. — In the Sedgwick Museum, Cambridge. 



Distribution. — Lower Greensand (Crackers) of Atherfield. Athcrfield Beds of 

 Peasemarsh. 



(5) 



(6) 



27 



21 mm 



20 



1*5 „ 



14-5 . 



9-5 „ 



Cypeina (Venilicaudia) peotensa, sp. nov. Plate XXI, figs. 4—7. Text-figs. 



20, 21. 



1845. Cypeina angulata, E. Forbes. Quart. Jouru. Geol. Soc, vol. i, p. 240 



(partint). 



