SANGUINOLITES CLAVATUS. 385 



Sanguinolites CLAVATUS, B. Ethericlge, juii., sp., 1876. Plate XL, figs. 7 — 14; 



Plate L, fig. 21. 



Leptodomus ? CLAVATUS, S. Etheviclye, juii., 187G. Anu. Mag. Nat. Hist., ser. 4,. 



vol. xviii, p. 102, pi. iv, figs. 9, 10. 

 Pandoea ? TYPiCA, R. Etlieridge,jiin., 1878. Quart. Journ. Geol. Soc, vol. xxxiv, 



p. 17, pi. ii, fig. 23. 

 Sanguinolites abdensis (?), Kirlchy, 1880. Ibid., vol. xxxvi, p. 586. 

 Pandora ttpica {?),Eiheridge, sen., 1888. Brit. Foss., pt. 1, Palfeozoic, p. 288. 



Specific Characters. — Shell small, very inequilateral, transverse, clavate, 

 arclied, gibbose anteriorly, compressed and narrowed posteriorly. The anterior 

 end is small, deep, swollen, and with rounded margin. The inferior border is 

 prolonged and convex, much elevated behind, where it rises rapidly to join the 

 posterior border. The posterior border is narrow and truncate, almost straight. 

 The postero-inferior angle is a rounded obtuse angle, and the postero-superior a 

 right angle. The hinge-line is long, nearly straight, but slightly concave 

 upwards. The umbones are gibbose, incurved and pointed, placed in the anterior 

 fourth of the valve, and elevated above the hinge-line. Passing downwards and 

 backwards from the umbo towards the postero-inferior angle is a more or less 

 well-defined ridge, which is often somewhat curved, separating the much 

 compressed and often concave dorsal slope from the rest of the valve. A well- 

 marked angular fold forming the upper margin of the valve passes backwards 

 from the umbo, separating the long escutcheon from the dorsal slope. In front 

 of the oblique ridge the valves are gently convex. Lunule well marked, narrow, 

 and elongate. 



Interior. — Pew details of the interior are known. The pallial line is entire 

 and the hinge appears to be edentulous and to have a long rolled edge pos- 

 teriorly. 



Exterior. — The surface is ornamented with concentric stride and folds of 

 growth, which become less apparent, and bend sharply upwards as they reach the 

 oblique ridge. Shell thin. 



Dimensions. — PI. XL, fig. 7, a specimen from Mr. Kirkby's zone 3, west of 

 Pittenweem [op. cit., p. 586), measures — 



Antero-posteriorly . . . .15 mm. 



Dorso-ventrally . . . .7 mm. 



From side to side . . . .6 mm. 



Localities. — England : the Redesdale Ironstone, Redesdale, Northumberland. 

 Scotland : shale above Craigleith Sandstone, Craigleith Quarry, near Edinburgh ; 



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