" F. R. Cov'per Reed — Salter's Undescribed Species. 147 



Eemarks. — A species which appears to be closely allied to this 

 form is Ft. fimbriata^ (McCoy), from the Silurian (Wenlock ?) of 

 Dingle, co. Kerry. This Irish species differs, however, in being less 

 elongated, in possessing a shorter posterior wing and a more acute 

 umbo, but the ornamentation of the surface closely agrees. McCoy 

 ■figures only a right valve. From Pt. subfalcata (Conr.) our species 

 differs in the regularity and strength of its concentric lamellation, 

 in its larger posterior ear, and the different shape of its anterior ear. 



Pterinea condor, Salter. (PI. VII, Figs. 6 and 7.) 



1873. Pterinea condor, Salter, n.sp. : Cat. Camb. Sil. Foss. Woodw. Mus., p. 169 



(« 809, a 810). 

 1891. Pterincea condor, Woods: Cat. Type Foss. Woodw. Mus., p. 89. 



There are three specimens labelled Fterinea condor by Salter, but 

 one of these (a 810) is probably due to a mistake, as it obviously 

 l)elongs to an entirely different species. The specimens all come 

 from the Lower Ludlow beds of Dudley and belong to the 

 Fletcher Collection. Salter describes it as having " very wide hinge 

 line, three inches broad." 



Diagnosis. — Shell transversely oblong, very inequivalve, flattened. 

 Hinge-line long, straight. Left valve weakly convex, flattened 

 posteriorly into large posterior wing, which is bluntly pointed 

 liehind, slightly excavated along posterior margin, and extended along 

 upper margin beyond body of shell. Hinge-line longer than shell. 

 Anterior ear very small, depressed below body of valve. Umbo 

 Mmall, prominent, rising above hinge-line. Distinct band along 

 iiinge-line marked off from posterior wing, representing ligaraental 

 facet. Surface of valve marked by faint concentric strife parallel to 

 margins. 



Eight valve (? of same species). Fig. 7, subquadrate, flattened. Upper 

 and anterior margins straight, meeting at angle of 120°, each furnished 

 with longitudinally striated, band-like area, of which the upper is 

 marked with five longitudinal shallow grooves, interrupted along 

 part of their length near anterior end. Posterior margin broadly 

 rounded, weakly emarginate at inferior angle. Inferior margin 

 rounded, meeting anterior margin at nearly a right angle. General 

 surface of valve feebly convex, especially in central part of hinge- 

 line. Oval muscular impression in anterior angle between upper 

 and anterior margins. 



Measurements. 



Left valve. mm. 



Width (along Mnge-line) 74 



Length 40 



Right valve. 



Width (along hiuge-line) 31 



Length ... ... ... 32 



Remarks. — This form most resembles Pterinea retrojlexa, var. 

 naviformis (Conr.), but differs in its more extended hinge-line and 

 more pointed posterior wing, as far as the left valve is concerned. 



1 McCoy : Silur. Foss. Irel., 1846, p. 21, pi. ii, fig. 7; Brit. Pal. Foss., 1851, 

 p. 263, pi. ii, figs. 3, da. 



