APPENDIX. 26 



RiiYNCHo.M-;u„- jrADRiPLiCATA, Zeiten, Sp. Plate A, fig. 22. 



Terebratula ql adriplicata, Zeiten. Dei Versteinerungen Wiirttembergs, pi. xii, 



fig. 3, 1832. 

 Riiynchonella qadripltcata, D'Orbigny. Prodrome, vol. i, p. 286, 1849. 



Diagnosis. Shell somewhat pentagonal, trilobed, wider than long; dorsal or socket valve more con- 

 vex than the ventral one, and almost equally divided into three lobes ; the central one which forms the 

 mesial fold is more or less produced beyond the lateral ones. In the ventral or dental valve a shallow sinus 

 extends to the front; beak short, acute, and incurved, so as almost to entirely conceal the foramen, which 

 lies contiguous to the hinge line and umbone of the opposite valve, the hinge line of the ventral valve in- 

 dents laterally the same portions of the dorsal one. Externally, each valve is ornamented by about twenty 

 large ribs, four of which occupy the mesial fold and sinus. Dimensions variable : length 16, width 17, 

 depth 1 1 lines. 



Obs. This species appears to be distinguished from R. tetrahedra, Sow., by its more equally 

 trilobed, and less gibbous appearance. It has been found by Dr. Wright, in the Inferior Oolite of Cleeve 

 Hill, near Cheltenham ; and Mr. S. P. Woodward discovered (some years ago) a British specimen in the 

 Inferior Oolite of Yeovil. Zieten mentions, likewise, that his types were obtained from the upper beds 

 of the Inferior Oolite, near Gosheim, and at Harras. M. d'Orbigny quotes his from the Terrain Bajocien. 

 at Saint-Maixent, Draguignan, Namers, Geniveaux, and the neighbourhood of Nantua. 



Plate A, fig. 22. A specimen, from the Inferior Oolite of Cleeve Hill, in the collection of Dr. Wright. 



Note. — I may here state that the greater number of specimens figured in this volume, to which no 

 named collection is appended, belong to my Cabinet. 



