370 MR. G. S. BRADY ON NEW OR IMPERFECTLY 



2. Cytheridea minima, n. sp. (PI. LVIII. fig. 10, a-d.) 



Valves triangularly ovate, convex. Dorsal margin well arched ; ventral nearly straight. 

 Extremities rounded. Dorsal aspect ovate. Surface perfectly smooth, milk-white. 

 Length 7*5 in. ("36 mm.). 

 Hab. West Indies (shallow water). One specimen. 



3. Cytheridea margaritea, n. sp. (PI. LVIII. fig. 6, a-d.) 



? Cytherina ovulum, Reuss, Haidinger's Abhandl. Band iii. p. 55, t. 8. f. 19. 



Carapace ovate, convex, very broad in front, suddenly narrowed behind. Dorsal 

 margin boldly arched ; ventral margin convex, slightly sinuated at the posterior third. 

 Extremities well rounded, the posterior being very narrow. Dorsal aspect broadly 

 ovate, pointed in front. Surface smooth, pearly white, thickly set with elevated papillse, 

 and marked, in the adult, with patches of white opacity. 



Length -^ in. ('57 mm.). 



Hab. Levant (sponge-sand). Many specimens. 



Very similar to Cytheridea aurantia, Baird, but more profusely papillose and less 

 tumid. It differs also in being higher in front than behind, the opposite being the case 

 with C. aurantia. It agrees precisely in shape with Cytherina ovulum, Reuss ; but the 

 character " superficie remote scrobiculata " prevents my referring it with certainty to 

 that species. I have seen no trace of pitting in C. margaritea. 



4. Cytheridea (?) curta, n. sp. (PI. LVIII. fig. 7, a, b.) 



Carapace subtriangular, reniform, convex, about once and a half as long as broad. 

 The dorsal margin strongly arched, somewhat gibbous in the middle. Ventral margin 

 slightly concave. Posterior border flattened, broad, rounded at the angles. Anterior 

 extremity narrow, rounded, and rather produced downwards. Seen from below, the 

 carapace is broadly ovate, scarcely once and a half as long as broad. Surface smooth, 

 sparingly papillose. 



Length -4^ in. ('6 mm.). 



Hab. West Indies (shallow water). One specimen. 



5. Cytheridea papillosa. Bosquet. (PL LVIII. fig. 8, a-g.) 



Cytheridea papulosa, Bosquet, Entom. Fossil, des Ter. Tertiair. p. 42. pi. 2. fig. 5. 

 Cythere bradii, Norman, Nat. Hist. Trans. Northumberland and Durham, vol. i. p. 15, pi. 5. figs. 5-8 

 (see also note, p. 28). 



Carapace subtriangular, ovate, rounded anteriorly, obliquely pointed behind. Dorsal 

 margin arched ; ventral margin straight or very slightly sinuated. Dorsal aspect oval 

 oblong, broadest in the middle, the extremities nearly equal. End view suborbicular. 

 Surface of valves white, smooth or sparingly punctate, bearing a few scattered papillse. 



