338 PfiOF. T. E. J02fES Olf THE OSTRACODA 



Cyprida valdensis, Jones, Geol. Mag. 1878, p. 110, pi. 3. 

 figs. 13-15. 



Length | mm., and 1 mm. 



Yalves subtriangnlarly obovate, nearly obovate, or subpyriform, 

 varying in the protuberance of the anterior hinge-joint. Both the 

 front and the hind margin are obliquely rounded ; but the latter is 

 more contracted than the former. Convex medially; edge-view 

 narrow-oval. Surface punctate ; punctatlons subcircular, easily 

 seen mth a lens (see also E. Porbes's letter to Mr. Bristow, above, 

 p. 314). The outer edge of the ventral margin of the left valve 

 overlaps that of the right valve. 



Notch and beak distinct, and often strong, but varying in inten- 

 sity. 



This species is broader (higher) and coarser than the typical 

 Cypridea valdensis (Fitton), figured by J. De C. Sowerby in the 

 ' Mineral Conchology,' pi. 485 (December 1824*), described there 

 at pp. 136-138, and referred, with doubt, to C'^/^^m/a^a, Desmarest. 

 The small (young) forms accompanying adult specimens of C. punc- 

 tata (no. 159) very much resemble C. valdensis. 



It is quite probable that some of the coarser valves referred to C. 

 valdensis by authors are really C . punctata., such as figs. 13, 14, 15, 

 pi. iii. Geol. Mag. dec. 2. vol. v. from the Subwealden Boring in 



2*. Ctpeidea ptj]s^ctata (Forbes). Var. posticalis, nov. (PI. YIII. 

 figs. 1-3, 6, 8.) 



Length generally 1mm. Pig. 8 represents a specimen g mm. 

 long. 



Although C. punctata often has a neat acute-oval edge-view, yet 

 very many individuals have the posterior extremity of each valve 

 thickened with a more or less pronounced marginal lump, thick and 

 round, low and broad, or narrow and faint, giving a blunt end to 

 the edge-view (fig. 3). The close-set subangular or subcircular 

 punctatlons are usually strongly marked. 



^**. Cypeedea punctata (Forbes). Yar. giebosa (Forbes). (PI. YIII. 



fig. 7.) 



Oypris gihbosa, Forbes, MS. July 18, 1851. 



Cypris gibbosa, Forbes in Lyell's Manual Elem. Geol. 5th edit. 

 1855, p. 294, fig. 334 a; id. Elem. Geol. 6th edit. 1865, p. 378, 

 fig. 368 a. 



Cypridea gibbosa, H. Woodward, Catal. Brit. Foss. Crust. 1877, 



p. 88: 



Length J mm. 



Here the middle of the valve is locally swoUen ; this is a variable 

 feature, not strong in fig. 7. See Forbes's letter, above, p. 314. 

 The specimen here figured is nearly obovate in outline, and has a 

 slightly thickened posterior edge (as in the foregoing yar. posticalis). 



* See " Dates de la publication des Especes," &c., par M. E. Eenevier, 

 ' Bullet. Soc. Yaudoise Scienc. Nat.' 2 Mai, 1855. 



