SALTER — CRETACEOUS FOSSILS, ABERDEENSHIRE. 87 



which are themselves covered by close sharp lines of growth, decus- 

 sated bv longitudinal striae. xA.n intermediate narrow rib lies between 

 each pair of costse. The shell seems to have been thick, the poste- 

 rior side steeply bent inwards, and probably (like the anterior slope) 

 free from ribs. The hinge-line had but few teeth, and only at the 

 outer angles. 



8. Cyprixa Fergusoni, Salter. PI. II. fig. 7. 



Moderately convex, rounded, with an elevated and pointed beak, 

 which is lateral and overhangs a shallow lunette ; anterior and poste- 

 rior sides rounded, the posterior slope arched, convex, not at all 

 angular or flattened above. Surface striated concentrically by close 

 sharp lines, and a few more prominent ridges of growth. Height, 

 1 inch ; length, 1 inch ; depth of two valves united, ^ inch. 



Most like in general shape to Venus Vassiacensis, D'Orb. (an 

 internal cast). But it is clearly not a Venus, as it has posterior 

 lateral teeth. Cijprina consohrina, D'Orb., is also like, but is 

 described as smooth, or nearly so. Our shell is closely and sharply 

 striate, and has not a very large lunette. 



9. Dentalium ccelatulum, Baily. PI. II. fig. 8. 

 Elongated; slightly curved, and gradually tapering posteriorly. 



The surface, which is preserved in a sandstone-mould, is ornamented 

 with both concentric and longitudinal striae closely set, producing a 

 finely reticulated appearance. Aperture somewhat oval. 



It differs from the Gault species Bentalium decussaturn, Sow., or 

 its cast, D. eUijiticum, in being straighter, and in having its surface 

 more finely reticulated, as well as in the absence of the more promi- 

 nent striations which occur on the posterior portion of that species 

 (W. H.B.). 



The two following species of Ammonites are figured, but are not 

 sufficiently perfect to make it worth while to give them names : — 



10. Ammonites, sp. PI. II. fig. 9. 



Discoid, whorls somewhat depressed and crossed by numerous 

 strong flexuous ribs, sometimes simple, but mostly dividing into two 

 about the middle of the side, and continuing over the rounded back. 



It is distantly allied to A. Pailletteanus, D'Orb. (Terr. Cret. 

 pi. 102), but that species has narrow ribs, none of which are distinctly 

 bifurcated (W. H. B.). 



11. Ammonites, sp. PL II. fig. 10. 



Discoid, whorls moderately rounded, with many flexuous ribs 

 which are prominent towards the umbilicus and bear a small com- 

 pressed tubercle at the point of bifurcation. The ribs are frequently 

 trifurcate, and one of them again branched from about the middle of 

 the side, so as to form groups of three or four ; umbihcus small. 



Apparently a smaller species than the last ; it is allied to A. Jean- 

 notii, D'Orb., /. c. pi. 56, — a species which has considerably closer 

 ribs, and occurs, I believe, in the English Gault (W. H. B.). 



