1867.] TATE SOTTTH-APEICAK POSSILS. 159 



occurs in the Great Oolite of Luc (Calvados), Vezelay (Yonne), 

 Grange-Henry, near Nantua, France*, and is moderately abundant 

 in the Cornbrash of Yorkshire f. 



Loc. Zwartkop River {Mr. H. Longlands), The specimen is 

 unique. 



Teigonia vatj, Sharpe (juvenis), et T. ventbicosa, Krauss, sp. (juve- 

 nis). PL YII. fig. 8. 



The character of the ornamentation clearly underwent a continuous 

 change during life in these two species of Trigonia (T. van and T. 

 ventricosa); I have therefore thought it necessary to figure these 

 species in their earliest stage of growth. 



*&• 



Teigonia Goldeussi, Ag. (juvenis). PL YII. fi^ 



Associated with the foregoing is the probably young shell of T. 

 Ooldfassi, Agassiz : certainly I should not be justified in assigning 

 it another appellation ; for the African shell is identical with figure 

 18 a, ]3late v. of Morris and Lycett's ' Monograph of the Great Oolite 

 MoHusca.' Hereafter, however, it may be found to be the young of 

 a distinct species. 



Loc. In a yellowish sandy shell-rock (a mass of Bivalves with 

 green and grey sand) on the Sunday's Biver (Buhidge). 



CoEBULA? Eoce:iaxa, spec. nov. PL YIII. fig. 8. 



Shell subglobular, smooth, shining ; umbones large, obtuse, mesial, 

 erect ; anterior side rounded ; lunule large, concave ; posterior side 

 very short, with a well-marked oblique carina and a truncated pos- 

 terior border ; the surface has numerous, delicate, irregular folds of 

 growth. 



Ohs. — The above diagnosis is nearly word for word that of Corhida 

 Agatha, D'Orb., as given by Lycett in his ' Supplement to the Great 

 Oolite Mollusca,' p. 65. That species, however, is of minute size ; 

 its posterior side has o. faintly marked carina, and its surface a few 

 folds of growth. 



Dimens. Length 1-19 millimetre, breadth 1-04 millimetre. 



Loe. In a yellowish-grey sandstone with calcareous cement, 

 Zwartkop Eiver (AtJierstone and JRuhidge). 



Ohs. — The dentition of Corhula ? Bockiana is unknown ; and the 

 species may hereafter be found to belong to Isocardia or to Oyprina ; 

 but, on account of its close affinity to Corhida Agatlia, I prefer to 

 let it remain with that generic title. 



The species is dedicated to Major Eock, who, with Mr. Stow, col- 

 lected and communicated several fossils from the Uitenhage Porma- 

 tion, and whose name I take this opportunity of associating with 

 South- African geology, 



* D'Orbigny, ' Prodrome,' vol. i. p. 308 (1850). 



t Lycett, ' Supplemeut to the Mollusca of the Great Oolite,' Palccont. Soc. 

 (1863), p. 49. 



