FROM TANGANYIKA AND KENYA 45 



gutitinguti creek, Tendaguru ; Upper Kimmeridgian, " Trigonia smeei " Bed. 

 Just W. of Mabokweni, 4 miles N.W. of Tanga, Tanganyika ; Kimmeridgian. 



Remarks. De Loriol and other authors have applied Roemer's name Gervillia 

 tetragona to a species which occurs in the Kimmeridgian of France and other Euro- 

 pean countries. Comparison of French specimens of that age with typical English 

 specimens of G. aviculoides , from the Corallian Beds (Oxfordian), has convinced me 

 that all belong to the same species. The East African specimens now recorded 

 cannot be distinguished from the European species. 



Genus GERVILLIA Defrance 1820 



Gervillia saggersoni sp. nov. 

 PI. 4, fig. 11 



Specific name. After Dr. E. P. Saggerson, of the Kenya Geological Survey. 



Diagnosis. Of medium size (length of holotype 62-5 mm.), broadly falciform, 

 not greatly oblique, diagonal from umbo forming an angle of about 15 ° with hinge- 

 margin. Hinge-margin about one-half of length of shell ; umbo protruding only 

 slightly and situated near anterior end of hinge-margin. Anterior and ventral 

 margins forming an uninterrupted, strongly convex curve ; posterior extremity 

 bluntly rounded. Body of shell, which attains a maximum width of about 17 mm. 

 in the holotype, evenly convex ; posterior wing narrow, flattened but not well 

 differentiated, with an obtuse outer angle. 



Holotype. No. L. 93622, consisting of internal and external moulds of a left 

 valve. A second internal mould (no. L. 93499) is too ill-preserved to rank as a para- 

 type. 



Localities and horizon. Korkai Hammassa, 19 miles E. of Takabba, N.E. 

 Kenya (type-locality), and Ogar Wein, 17 miles N.W. of Wergudud, N.E. Kenya ; 

 Oxfordian, Golberobe Beds. 



Remarks. This form was originally recorded (Saggerson & Miller 1957 : 14) as 

 Gervillia cf. monotis Eudes-Deslongchamps, but the true G. monotis, from the Bathon- 

 ian of Europe, is a smaller form with a narrower body. The most closely comparable 

 species is Gervillia pancici Radovanovic (1900 : 64, pi. 1, figs. 4, 5), from the Lower 

 Lias of Yugoslavia, but this appears to have a longer dorsal margin. In view of 

 their falciform outline these forms seem better included in Gervillia than in Gervillella. 



Family PINNIDAE 



Genus PINNA Linnaeus 1758 



Pinna buchii Koch & Dunker 



PL 4, fig. 9 



1837. Pinna buchii Koch & Dunker : 33, pi. 2, fig. 18. 



1869. Pinna buchii K. & D. ; Brauns : 230. 



1899. Pinna buchii K. & D. ; Greppin : 99, pi. 13, figs. 5, 6. 



