402 DR. G. S. BEADY ON THE OSTEACODA 



triangular, with rounded angles and broad base, tapering upwards; surface of the 

 shell smooth, marked by a few very small, distant punctations, and by exceedingly faint 

 longitudinal striae. Length -^^ inch (0-5 millim.). 



The shell of the male (fig. 5 e) is much more attenuated and tapering at the hinder 

 extremity. 



This species occurred very sparingly in the two beds of the Sables inferieurs. It is 

 very closely allied to (though somewhat different iu shape from) C.fulva, a species 

 described by myself and Mr. Eobertson from dredgings made at the Scilly Islands. I 

 liave much pleasure in naming this species in honour of M. Ernest Vanden Broeck, not 

 only as a personal acknowledgment of his courtesy to myself, but as a tribute to his 

 services to science in the investigation of the geology of Belgium &c. 



Cythekuka coenuta, Brady. (Plate LXVI. figs. 7 a-7 d.) 



Cythei-ura cornuta, Brady, Monogr. Kecent Brit. Ostrac. p. 445, pi. xxxii. figs. 12-15 (1868) ; Brady, 

 Crosskey, and Robertson, Monogr. Post-tert. Entom. Scotland, &c., p. 199, pi. xiii. figs. 23-25 

 (1874). 



Carapace of the male, as seen from the side, oblong, rhomboidal, nearly equal in height 

 throughout ; height equal to half the length ; anterior extremity rounded, posterior 

 obliquely truncate and produced above the middle into a large obtuse beak ; dorsal and 

 ventral margins nearly straight. Seen from above, the outline is ovate, with two rect- 

 angular alseform projections behind the middle ; anterior extremity acutely, posterior 

 obtusely pointed ; width equal to about two thirds of the length. End view subtri- 

 angular, with convex and irregularly crenate sides. Shell-surface sculptured with 

 conspicuous waved longitudinal ridges, and having a rectangular transverse ridge near 

 the posterior extremity, which ridge ends near the ventral margin in a strong cornute 

 projection. Length g^- inch (0-44 millim.). 



One or two examples only of this species have been found in the " zone a Bryozoaires " 

 and "zone k Panopcea menardi." The specimen figured I judge, from its elongated 

 form, to have been probably a male. 



Genus Cttheropteeon, G. O. Sars. 

 Valves mostly subrhomboidal, tumid, unequal, and different in shape, the right more 

 or less overlapping the left on the dorsal margin ; surface of the shell smooth or 

 variously sculptured, punctate, papillose, reticulated, or transversely rugose; ventral 

 margin produced laterally into a prominent rounded or spinous ala, posterior extremity 

 into a more or less distinct beak ; hinge formed by two small terminal teeth on the 

 right, and by a minutely crenated median bar on the left valve. Upper antennae shortly 

 setose and composed of five joints ; penultimate joint elongated, and bearing on the 

 middle of the anterior margin two hairs ; lower anterniaj distinctly 5-jointed. Flagellum 

 long. Mandibles of moderate size. Palp 3-jointed. Branchial appendage bearing two 



