BIVALVIA. 59 
Lvcrna? Burronensis, Zyc. Tab. XL, figs. 20, 20 a, 20 4. 
Testa suborbiculata, depressa, umbonibus subangulatis antrorsum curvatis, latere postico 
area depressiuscula, superficie striis tenuibus concentricis crebris notatis. 
Shell suborbicular, depressed ; umbones antero-mesial, angulated at their extremities, and 
curved forwards ; the posterior side has a depressed, oblique area, without any angle ; the 
surface has very delicate, closely arranged, regular, concentric striations ; the hinge-border 
is short, and slightly curved. 
As the hinge has not been exposed, some doubt may exist whether it is really a 
Lucina; the umbones are more produced than is commonly seen in that genus. 
Geological Position and Locality. The Forest Marble of Burton Bradstock, Dorset, in 
the collection of W. Walton, Esq. 
Lucina Brant, Bean, sp. Tab. XXXVIII, fig. 3. 
Astarte Rotunpata, Bean. Mag. Nat. Hist. 1839, non Roemer. 
Testa tumida ovato-obliqua, umbonibus antemedianis, magnis, incurvis, margine cardinal 
oblique-declivi, curvato, margine antico brevi, arcuato curvato ; valvis striis rregularibus, 
plicisque semel instructis. 
Shell somewhat inflated, oblique, ovate; umbones prominent, obtuse, incurved, placed 
anterior to the middle of the valves ; hinge-margin lengthened, curved, sloping obliquely 
downwards ; anterior margin short, rounded ; lunule very slightly excavated ; the surface of 
the valves has irregular, concentric striations, and also a few large plications of growth. 
The interior has not been exposed, but neither the hinge-margin nor the anterior border 
possesses the usual characters of Astarte, the lunule being nearly obsolete. It is shorter 
and more convex than Zucina crassa, nor does it nearly resemble any other contempo- 
raneous species. 
Height and lateral diameter nearly equal; diameter through both the valves, one 
third less. 
Geological Position and Locality. The Cornbrash of Scarborough, in the collection of 
Mr. Leckenby. 
Corsis Neprunt, LZyc. Tab. XXXV, fig. 19. 
Testa transverse ovali subequilatera, concentrice costata, margine cardinali curvato, 
oblique declivi, lunula magna excavata, umbonibus medianis subdepressis, antrorsum curvatis ; 
costis concentricis regularibus angustis, striisque interstitiis instructis. 
Transversely oval, convex, nearly equilateral; umbones rather depressed, curved for- 
