Vol. 67.] KAINOZOIC MOLLUSCA FROM CYRENAICA. 653 



JEquipecten zitteli (Fuchs). 

 Miocene (Aquitanian). Ain Sciahat. (See p. 632.) 

 Fig. 7. External view of a specimen. 



8. Sculpture details of the same. X 4. 



Ostrea ventilabrum Gk>ldf'uss. 

 Oligocene or Eocene (Priabonian). Near Slonta. (See p. 642.) 

 Fig. 9. A spreading and depressed form of a lower valve. 



10. Another specimen, showing a more arcuate character. 



11. An upper valve belonging to a small specimen. 



Corbis lamellosa (Lamarck). 

 Oligocene or Eocene (Priabonian). Near Slonta. (See p. 648.) 

 Fig. 12. External view of a fragmentary valve. 



13. Sculpture of the same specimen, showing the characteristic vertical 

 costas between the concentric ribs. X 3. 



Plate XLVI. 



Mquipecten cyrenaicus, sp. nov. 

 Oligocene or Eocene (Priabonian). Ain Sciahat (above camp). (See p. 644.) 

 Fig. 1. External view of a specimen representing a lower or right valve, 

 showing the V-shaped furrows. 

 2. Sculpture details of the same. X 3. 



Pecten arcuatus (Brocchi). 

 Oligocene or Eocene (Priabonian). Messa, and near Bint. (See p. 643-) 

 Fig. 3. Outer aspect of a fragmentary lower valve from Messa. 



4. Profile of the same, showing convexity. 



5. Sculpture details of the same specimen. X 3. 



6. External view of an upper valve of another specimen, from near 



Bint. 



Vulsella sp. 

 Oligocene or Eocene (Priabonian). South-east of Merj. (See p. 645.) 

 Fig. 7. Valve of Ungulate contour, resembling V. crispata Fischer. 



Gisortia gigantea (Minister). 



Oligocene or Eocene (Priabonian). Mersa Susa. (See p. 640.) 

 Fig. 8. Front aspect of a small form in the condition of a natural cast. 



Vasum cf. frequens (Mayer-Eymar). 

 Oligocene or Eocene (Priabonian). Messa. (See p. 641.) 

 Fig. 9. Front aspect of a specimen (natural cast), showing traces of 

 columellar plications. Reduced to half the natural size. 



Rostellaria sp. 

 Oligocene or Eocene (Priabonian). South-east of Messa. (See p. 640.) 

 Fig. 10. Dorsal view of a limestone cast. 



Euspira cf. possagnensis Oppenheim. 

 Oligocene or Eocene (Priabonian). East of Ain Hafra. (See p. 638.) 

 Fig. 11. Dorsal view of a natural cast, showing the extensive basal whorl. 

 Beduced to half the natural size. 



2y2 



