EXPLANATION OF THE PLATES AND WOOD-CUTS. 



Fig. 3. Area hybrida. Transversely oblong, oblique, longitudinally costated ; costae 

 strongly marked with the lines of growth, — those on the anterior side, furrowed 

 along the middle ; area narrow. Length 1 1 lines, width 14 lines. 



Nearly related to the recent A. rhomhea, but with a narrower area between the 

 beaks, approaching to A. Indica of Linnaeus. 



Loc. Baboa Hill. 

 Fig. 4. Pectunculus Pecten. Orbicular, convex, ribbed ; ribs about 30, radiating, 

 crenated by the lines of growth ; hinge-line short. Length 10 lines, width 

 1 1 lines. 



Very nearly like P. pectinatus of Lamarck, but with more numerous and more 

 distinctly granulated rays. 



Loc. Baboa Hill. 

 Fig. 5. Nucula Baboensis. Transversely oval, convex, smooth?; lunette sunk ; beaks 

 nearest the anterior side. Length f inch, width 1 inch. 



Nearly resembling N. Bowerbankii (Geol. Trans. 2nd series. Vol. v. 136. PI. 8. 

 f. 11.) but not truncated or pointed below the lunette. 



Loc. Baboa Hill. 

 Fig. 6. Pecten leein-costatus. Short, smooth, radiated ; radii about 20, large, equal to 

 the spaces between them ; ears large ; inside furrowed. Length 1 inch 4 lines. 



Length a little less than the width, but the ears enter so much into the sides that 

 they confine the beaks into a small angle, and make the form appear more trans- 

 verse than it really is. 



Loc. 

 Fig. 7. Ostrea callifera. (Lam. Hist. Nat. Vol. vi. p. 218. Deshayes, Coq. Fossiles 

 des Env. de Paris, Vol. i. 339. PI. LL, f. 1, 2.) ? A very ponderous shell, with 

 only a shallow cavity for the animal. Length 3^ inches, width 2| inches, thickness 

 of the shell above an inch and a quarter. 



The figure is reduced to two-thirds of the natural dimensions. 



Loc. Wag^-ke-Pudda. 

 Fig. 8. Ostrea orbicularis. Orbicular, plaited ; both valves convex ; plaits angular, 

 repeatedly forked ; surface imbricated. Length and width about two inches, re- 

 sembling O. Flabellulum, but more regularly and finely striated. See p. 302. 



Loc. Luckput. 

 Fig. 9. Neritina grandis. Short-conical, smooth ; spire concealed ; aperture very 

 large ; base convex, its margin rounded. Diameter 3 inches, height 1| inch. 

 Reduced in the figure to two-thirds the diameter. 



This resembles N. SchmidelUana, but has a larger aperture in proportion and a 

 less excentric apex ; it is also higher. The specimen is little more than a cast, and 

 does not exhibit the edge of the inner lip, but still it shows the attachment of the 

 ligament projecting from the lower surface, and that the aperture occupied more 

 than half the base. 



Loc. Wag^-ke-pudda. 

 Fig. 10. Globulus obtusus. Globose, with a very short spire ; whorls about G ; aper- 

 ture ovate-elongated, pointed above ; umbilicus open, narrow. Height 1 inch, 

 diameter the same. 



