PLATE 9 



Figs. la, b, c. Lopha costata (J. de C. Sowerby). Upper Lias, Toarcian. Didimtu hill, 

 2 miles S. of Bur Mayo, N.E. Kenya. LL. 35025 : a, left valve ; b, ventral view ; 

 c, right valve, all x 1 . . . . . . . . . . p. 66 



Figs. 2a, b. Lopha olimvallata nom. nov. Upper Lias, Toarcian. Didimtu hill, 



2 miles S. of Bur Mayo, N.E. Kenya. LL. 35026 : a, interior of left valve ; b, posterior 

 side of left valve, attached to sheet of fibrous calcite, both x 1 . . . p. 68 



Fig. 3. Liostrea polymorpha (Miinster). Upper Oxfordian. Lihimaliao creek, 

 Mandawa area, Tanganyika. Left valve, LL. 35102, x 1 . . . . p. 72 



Fig. 4. Lopha solitaria (J. de C. Sowerby). Upper Oxfordian, Seir Limestones. Dusse, 

 i£ miles S.E. of Rahmu, N.E. Kenya. LL. 92224, x 1 . . . . . p. 69 



Fig. 5. Lopha gregarea (J. Sowerby). Upper Kimmeridgian, Dakacha Limestones. 



3 miles N.E. of Melka Dakacha, N.E. Kenya. L.92179, x 1 . . . p. 68 

 Figs. 6a, b. Liostrea (Catinula) alimena (d'Orbigny). Callovian [?-Lower Oxfordian], 



Muddo Erri Limestones. 10 miles W. of Rahmu, N.E. Kenya. L. 92137 : a, left valve ; 

 b, posterior view, both x 1 . . . . . . . . . . p. 72 



Figs, ja, b. Liostrea polymorpha (Miinster). Upper Oxfordian. Lihimaliao creek, 

 Mandawa area, Tanganyika. LL.35103 : a, left valve, with second specimen broadly 

 attached to it : b, right valve, both x 1 . . . . . . . . p. 72 



Figs. 8a, b. Lopha cf. intricata (Contejean). Oxfordian, Rahmu Shales. b\ miles 

 S.S.W. of Rahmu, N.E. Kenya. L. 83899 : a, large attachment area of left valve ; b, right 

 valve, both x 1 . . . . . . . . . . . . p. 69 



