172 Appendix to Part I. 



first sight I thought it might be identical with it ; it may be easily 

 distinguished, however, by its being destitute of the fold in the 

 centre of the columella so conspicuous in those shells. There is 

 only one specimen, which has unfortunately lost the lower part of 

 the outer lip, so that it is impossible to describe the form of the 

 aperture. 



3. Venus soiulans. G. Sowerby. 



Testa rotimdatd, vcntricosd, Icsviusculd, crassd; costis ob/usis, 

 latiusculis, concentricis, a?itice posticeque tuberculatim. solutis ; 

 area cardinali posticd altera valves latiusculd ; impressione 

 subumbonali posticd circular i: long. 18, alt, "TS, lat, 1*5, 

 poll. 



A shell which is intermediate in its characters, taking its 

 place between the Venus verrucosa of the British Channel and the 

 V. rosalina of Rang of the western coast of Africa, but sufficiently 

 distinguished from both by its broad, obtuse, concentric ribs, which 

 are divided into tubercles both before and behind. It is also of a 

 more circular form than either of those species. 



The following Shells, from the same bed, as far as they can 

 be distinguished, are known to be recent species : — 



4. Purpura Fucus. 



5. Amphidesma australe. Sowerby. 



6. Coxus vexulatus. Lam. 



7. Fissurella coarctata. King. 



8. Pekxa — two odd valves, but in such condition that it can- 

 not be identified. 



9. Ostrea cornucopre. Lam. 



10. Arca ovata. Lam. 



11. Patella xigrita. Budgin. 



12. TURRITELLA BICXXGULATA ? Lam. 



13. Strombus — too much worn and mutilated to be identified. 



14. Hippoxtx radiata. Gray. 



15. Natica uber. Valenciennes. 



16. Pectex, which in form resembles opercularis, but which is 

 distinguishable by several characters. There is only a single valve, 

 wherefore I cannot consider myself warranted to describe it. 



J 7. Pupa subdiaphaxa. King. 

 18. Trochus — indeterminable. 



