CYPRIS. 127 



anterior of which is acutely, the posterior subacutely, pointed. End-view very broadly 

 ovate, pointed above and below. The right valve considerably overlaps the left. 

 Surface of the shell smooth or very finely punctate. 



Length of fossil specimens 515th, recent ^th, of an inch. 



Distribution. Becent. — Yorkshire moors. 



Fossil. — Crofthead, Scotland. 



Some doubt may, perhaps, attach to our identification of these specimens, none of 

 which were quite perfect, and most merely worn and separated valves ; but except in size 

 they approach very closely to the form described by one of the present authors under 

 the name Ct/pris cinerea. Our written description is taken from recent specimens, but 

 will be found to agree very closely with the figure taken from a fossil carapace, and given 

 in Plate II of this Memoir. 



7. Cyphis GiBBA, Bamdohr. Plate XV, figs. 5, 6. 



1808. Cypkis GIBBA, Bamdohr. Magaz. d. Gesellsch. naturforsch. Freunde zu 



Berlin, ii, p. 91, t. iii, figs. 13 — 17 (/c?e Jones). 

 1856. — — Jones. Mon. Entom. Tertiary Form., p. 15, pi. i, figs. 3 



a — -f, and Woodcut, fig. 1, p. 16. 

 1868. — — Brady. Monog. Recent Brit. Ostr., p. 369, pi. xxiv, figs. 47— 



54, and pi. xxxvi, fig. 2. 

 1850. ? Cytherina expansa, Reuss. Haidinger's Abhaudl., Band iii, p. 60, taf. ix, 



fig. 11. 



Valves, as seen from the side, oblong, subreniform, nearly equal in height through- 

 out, marked usually by two deep transverse furrows extending from the anterior half of 

 the dorsum to near the middle of the valve ; sometimes also bearing a prominent tubercle 

 on the posterior portion of the valve ; extremities well rounded and nearly equal, the 

 posterior often bordered below the middle with a series of small, sharp, but irregularly 

 placed spines. Superior margin nearly straight, inferior deeply sinuated in the middle ; 

 seen from above the shape is oblong-ovate, compressed, width equal to rather more than 

 one third of the length ; obtusely pointed in front, rounded off behind, the lateral sulci 

 showing as marginal indentations. SheU thick and strong, closely and rather coarsely 

 punctate, usually whitish or buff coloured. 

 Length, -^th of an inch. 



Distribution. Becent. — Great Britain, Germany, Holland. 



Fossil. — England : Cambridge Fens, Grays, Clacton, Reculvers, Hornsea, Whittlesea, 

 Branston Pen. Scotland : Crofthead, Dipple, Terally. 



