EDMONDIA LOWICKENSIS. 297 



middle third of the valve. Passing downwards from the umbo to the posterior 

 inferior angle is an obscure rounded ridge, posterior to which the valve is rapidly 

 compressed into the margin. Elsewhere the valve is regularly and evenly convex, 

 the point of greatest curvature being high up about the centre of the transverse 

 diameter. The dorsal slope is much compressed. 



Interior. — The anterior adductor muscle-scar is round, shallow, deeper inter- 

 nally, where it is separated from the umbonal hollow by a slight ridge, and situated 

 just within the margin of the antero-superior angle. The posterior scar is 

 almost obsolete. The pallial line is entire and marginal. The hinge-plate has 

 attached to it the elongate flattened ossicle which is placed in the hollow of the 

 umbo, and represented in the cast by a narrow elongate slit. The interior of the 

 shell is marked by shallow grooves and obsolete ridges, crossed by very fine 

 regular radiating lines. 



Exterior. — The surface is covered by very fine, regular, close, concentric lines 

 of growth, with here and there an approach to sulcation. 



Dimensions. — Fig. 1, PI. XXXIII, from Thornliebank, measures — 

 Antero-posteriorly . . . .32 mm. 



Dorso-ventrally . . . .23 mm. 



Laterally . . . . .16 mm. 



Localities. — England : one of the Limestones of Lowick and the Four Laws Lime- 

 stone at the Coombs, Northumberland. Scotland : the Upper Limestone series of 

 the Girtle quarry near Dairy, and Thornliebank ; Index Limestone, Hullerhirst. 



Observations. — This species was referred by M'Coy to Goldfuss's Sanguino- 

 laria phaseolina from the Eifelian of the Continent. I cannot see any reason for 

 such an opinion on comparing the suite of British specimens with the figure; and 

 although the meagre description does to a certain extent coincide with that given 

 by M'Coy, I have thought it wiser to give a new name to the species. Goldfuss says 

 that his species has " striae radiantes/' which is not the case with the external shell 

 of E. Lowickensis. Giebel gives the stage for Goldfuss's 8. phaseolina as " Grau- 

 wachenformation," in his ' Repertorium zu Goldfuss's Petrefakten Deutschlands,' 

 p. 84. The species is retained by Benshausen in his work ' Die Lamellibrauchiaten 

 des rheinschen Devon,' under the name Janeia phaseolina, and his figures amply 

 demonstrate that Groldfuss's and M'Coy's shells are entirely different. The 

 specimens on which M'Coy founded his description are from Lowick, and are in 

 the Woodwardian Museum, Cambridge. They are all casts, and exhibit the 

 internal characters very well. Fortunately a very fine example has been ob- 

 tained by Mr. J. Neilson at Thornliebank, which has the test preserved (fig. 1, 

 PI. XXXIII), and I have obtained a small suite of specimens from the Girtle quarry 

 near Dairy. Mr. J. Dunn has obtained a small fragment from the limestone at the 

 Coombs, south of Redesdale village, which I regard as the Four Laws limestone, 



