386 DR. G. 8S. BRADY ON THE OSTRACODA 
proportions of the shell are also liable to considerable variation during the process of 
growth. 
Cythere jurinei occurs in moderate abundance in the Pectunculus and Panopea- 
menardi beds (Sables inférieurs), also in the Trophon-antiquum bed (Sables supérieurs). 
CYTHERE PLICATA, Miinster. (Plate LXV. figs. 5 a—-5 d.) 
Cythere plicata, Minster, Jahrb. fiir Mineralogie, &c., 1830, p. 63, and Neues Jahrb. &c. 1835, 
p- 446 (fide Jones et Bosquet). 
Cythere plicata, Romer, Neues Jahrb. fiir Min. &c. 1838, p. 518, pl. vi. fig. 26 (fide Jones et Bosquet). 
Cypridina laticosta, Reuss, Haidinger’s Abhandl. iii. p. 87, pl. ii. fig. 18. 
Cythere plicata, Bosquet, Entom. fossil. des terr. Tertiair. de la France, &c., p. 60, tab. ii. fig. 13. 
Cythere plicata, Jones, Tertiary Entomostraca of England, p. 32, pl. iv. fig. 16, and pl. v. figs. 8a— 
8d (? pl. v. fig. 17). 
Cythere plicata, Egger, Die Ostrak. der Miocin-Schichten bei Orenburg (1858), p. 24, pl. v. fig. 9 
(icones male). 
Cythere plicata, Speyer, Die Ostrac. der Casseler Tertiirbildungen (18638), p. 29, pl. iv. figs. 2a,6,¢, d. 
Carapace, as seen from the side, oblong, subquadrangular; length equal to rather 
more than twice the height. Anterior extremity wide and well rounded, posterior 
narrowed, and armed with three or four blunt teeth ; dorsal and ventral margins nearly 
straight in front, but converging towards the posterior extremity. Seen from above, 
oblong-ovate, tapering gradually toward the front, and abruptly behind; extremities 
obtusely pointed ; greatest width near the hinder extremity, and equal to half the length. 
End view irregularly quadrate, the lateral margins having each a large central promi- 
nence. The valves are marked by three large, curved and rounded longitudinal ribs, 
the central one being the most prominent: the ribs themselves are smooth; but the 
intermediate furrows are sculptured with large rounded pittings. The hinge-line is 
marked by a deep depression. Length 3/9 inch (0°85 millim.). 
C. plicata occurs in moderate abundance in both beds of the “ Sables moyens” and 
much more rarely in the Panopwa-bed (Sables inférieurs). It is noted by Professor 
Rupert Jones as occurring in the middle Eocene of the Isle of Wight and Hampshire ; 
and the same author states that “it has been found in the Miocene deposits of Dax, 
and in the Eocene of France, Belgium, North-western Germany, Bohemia, Austria, and 
Moravia.” In some of these deposits it seems to be very abundant, and, indeed, may be 
looked upon as one of the commonest and most widely distributed of the Tertiary 
Ostracoda. It is, moreover, very distinct in its characters, and scarcely likely to be 
confused with any other species, at any rate in its typical form. 
CYTHERE BELGICA, nov. sp. (Plate LXV. figs. 3a, 3 6.) 
Carapace, seen from the side, subrhomboidal, somewhat higher in front than behind ; 
height equal to half the length ; extremities obliquely rounded ; dorsal margin straight, 
sloping gently from before backwards; ventral slightly convex. Outline, seen dorsally, 
