Mr.D. Sharpe on PalcBOzoic Fossils from South Africa. 207 



man's Kloofs in the Cape of Good Hope, which has considerahle affinity to this 

 shell ; it is S. Capensis, Von Buch, ' Baren-Insel,' p. 12. fig. I. It differs from S. 

 Antarcticus in having the mesial fold and sinus broader than in our species, and in 

 having the beak of the dorsal valve bent over, and the area deeply curved ; it also 

 wants the imbricating lines of growth. 



Spirifer Orbignii, Morris & Sharpe, Quart, Journ. Geol. Soc. vol. ii. pi. xi. fig. 3. 

 PI. XXVI. figs. 3, 4, & 6. 



S. testi semi-ovali, subaequivalvi : costis 16 rotundatis, elevatis, concentrice imbricatis : costa 

 media ventrali lata, elevata, imbricata, medio sulcata ; sulco medio dorsali lato, profundo, 

 rotundato, medio costato : area cardinal! angusta, latitudine valvarum. 



Shell transversely semi-oval, nearly equivalved ; with about sixteen prominent, 

 rounded ribs, imbricated by strong concentric lines of growth : mesial ridge of the 

 ventral valve large, prominent, and imbricatedf, and marked by a slight medial 

 furrow; mesial furrow of the dorsal valve broad, deep, and rounded, with a very 

 slight medial rib : hinge-area of the breadth of the shell, narrow. 



Breadth 2^ to 3 inches ; length 1 to l^ inch. 



Found abundantly in the hard grey siliceous rock of the Warm Bokkeveld, with 

 the preceding species ; and also found in the Falkland Islands by Mr. C. Darwin. 



I presume that this is the species which Dr. F. Sandberger has referred to Spirifer 

 macropterus, Goldf., var. mucronatus, but I cannot concur in that view. All the 

 African specimens have the uniformly curved outline represented in the figures, 

 while S. viacropterus has the outline of each wing in a curve more or less sigmoidal : 

 the interiors of the valves are also different ; S. Orbignii has a greater thickening 

 of the interior of the dorsal valve towards the hinge, having the casts of the 

 muscular impressions more prominent. The slight rib in the middle of the mesial 

 furrow and the furrow in the mesial ridge of S. Orbignii (which should be more 

 marked in the figures) are also distinguishing characters. 



Fig. 3, cast of the interior of the dorsal valve ; fig. 4, cast of the interior of 

 the ventral valve ; fig. 6, exterior of the ventral valve, from a gutta-percha mould 

 of an impression of the shell. 



Orthis palmata, Morris & Sharpe, sp. PI. XXVI. figs. 7-10. 



Atrypa palmata, Morris & Sharpe, Quart. Journ. Geol. Soc. vol. ii. pi. x; fig. 3. 



O. testa subhemisphaerica, radiatim costato : valva ventrali depress^, dorsali gibbosa : costis 

 14-16 rotundatis, elevatis, simplicibus, sulcis rotundatis intermediis subsequalibus : linea cardi- 

 nali subrecta, breviuscula. 



* Kokman's Kloof is a pass in the mountains north of Swellendam. 



t In the specimen fig. 6 the imbrication has been rubbed off the mesial ridge, and the furrow down 

 it is also lost. 



VOL. VII. SECOND SERIES. 2 F 



