Mr. D. Sharpe on Secondary Fossils from South Africa. 195 



distant than the rest ; by the rounding-ofF of its lower posterior margin ; and its 

 less marked cardinal area : it differs from P. similis, Ag., of the Middle Oolite of 

 the Jura, in wanting ribs on the anterior portion of the shell : it is also near to P. 

 decemcostata, Romer, of the Upper Oolite of Germany. Should the above-men- 

 tioned forms be hereafter united as one species, the African shell must be placed 

 with them. 



Myacites ? Bainii, Sharpe. PI. XXII. fig. 7. 



M. testa tenui, transversim ovato-elongata ; antice posticeque hiante : umbonibus subanticia, 

 prominulis : margine ventrali recto. 



Shell thin, transversely elongated ; gaping and rounded at both ends ; somewhat 

 compressed in the middle, and with a straight ventral margin : lines of growth 

 irregular. 



Length 1^^ inch ; breadth 2^ inches ; thickness f ths of an inch. 



Found at Sunday River, in greenish shelly grit. 



An inconspicuous shell, of which the true characters can only be ascertained 

 after the interior of the valves shall have been seen. 



Ceromya papyracea, Sharpe. PI. XXII. fig. 8. 



C. testa tenuissima, ovato-rhomboidea, ventricosft ; antice abbreviate, inflata ; postice com- 

 pressa, subproducta ; margine cardinal! recto : umbonibus anticis, prominentibus, incurvis : 

 lineis concentricis crebris. 



Shell very thin, nearly rhomboidal, ventricose ; anterior end short and inflated, 

 with large incurved umbos ; posterior end somewhat produced and gradually 

 flattened : cardinal margin straight ; ventral margin slightly rounded : valves 

 slightly unequal, covered with fine, close-set, regular, concentric lines of growth, 

 which on the middle of the right valve are crossed by a few very faint, radiating 

 lines, which are slightly marked on the internal cast. 



Length l^inch; breadth 1^ inch j thickness 1 inch. 



Found at Zwartkop River. 



I place this species in the genus Ceromya with some doubt ; the extreme thin- 

 ness of the shell excludes it from Isocardia ; the slight inequality of the valves, 

 the faint rays on the right valve, and the slightly waved outline of the posterior 

 margin, indicating that it is probably a gaping shell, bring it nearer to Ceromya than 

 to Cardiomorpha. 



Cyprina rugulosa, Sharpe. PI. XXII. fig. 9. 



C. testa rhomboideo-ovata, antice laeviuscula, declivi, postice inflate ; concentrice rugosa : 

 umbonibus anticis prominulis : dente cardinali lateral! obsoleto. 



Shell thick, transversely ovato-rhomboidal ; inflated in the middle and posterior 



