532 DR WHEELTON HIND ON 



the shell figured by him, Tia/riconcha scalariformus (pi. xxxviii. fig. 1), from the Upper 

 Middle Devonian of Martenberg, shows a very close resemblance indeed between the 

 Ordovician and Devonian species. 



Barrande's genus Slava has the precedence of date, and must therefore stand. 



He refers Sower by's Cardiola fibrosa to the genus, and figures it and one other 

 species, S. bohemica, both from Stage E of the sequence he established for Central 

 Bohemia. 



Slava fibrosa, Sow., 1839. (PI. V., figs. 17-19, 19a.) 



Cardiola fibrosa, Sow., 1839, Sil. Syst., p. 617, pi. viii. fig. 4. 



Mytilus semirucjatus, Portlock, 1843, Rep. Geol. Londonderry, p. 430, pi. xxv. A, fig. 7. 



Cardiola „ M'Coy, 1855, Brit. Pal. Foss., p. 282. 



Slava ,, Barrande, 1881, Syst. Sil. de la Boheme, vol. vi. p. 154. 



Specific Characters. — Owing to the crushed condition of all specimens, the shape 

 cannot be determined from them. They all show remains of medium-sized shells which 

 have few concentric sulci and ridges in the upper half, and a finely radially striate 

 portion below, the latter being of much greater extent. The umbones were pointed. 

 The concentric ridges are often composed of two close portions separated by a fine 

 linear groove. 



Dimensions cannot be given, owing to the imperfection of the specimens. 



Locality. — Bargany Pond Burn and Penkhill, said to be Upper Llandovery. 



Observations. — Slava fibrosa is a very peculiar shell, easily recognised by the 

 characteristic ornament of transverse sulci above and fine radiating striae below. 

 Good figures are given in the Silurian System (op. supra cit.). If not identical, the 

 Bargany examples are closely allied. The peculiar reduplication of the concentric 

 ridges is not shown in the drawings of previous writers, but I doubt whether this 

 character is more than a variation of growth. 



Murchison stated that this shell was a Lower Ludlow species (Siluria, 3rd ed., p. 255). 

 Sowerby stated that C. fibrosa was one of two species " very characteristic of the 

 lower members of Upper Silurian rocks over wide tracts." The list of fossils from the 

 Silurian rocks of the South of Scotland in the Fauna, Flora, and Geology of the Clyde 

 Area compiled for the Meeting of the British Association, quotes the species as occurring 

 at Penwhapple and Straiton (p. 437) ; but in the same work, at pp. 425 and 429, Straiton 

 is referred, in the tables of strata, to the Wenlock series, and Bargany to the Tarranon 

 series. A.s M'Coy points out (op. supra cit.), the radiating striae can be traced in some 

 specimens to the umbo, but they are almost obsolete on the ridges and practically 

 absent in the sulci. M'Coy's work may be referred to for a complete description of the 

 species. 



It has occurred to me that the peculiar figures of Mytilus semirugatus, Portlock 

 (<>l>. cit.), may belong to this species. 



