REPORT ON THE OSTRACODA. (35 



subovate, -with, nearly parallel sides, converging rather abruptly towards the extremities, 

 which are nearly equal and obtusely pointed; width less than the height; end view 

 subc[uadrate, with a well-marked ventral keel. The surfece of the shell is marked 

 irregularly with small rounded depressions, and also round the margins with sinuous 

 grooves, which on the ventral aspect are disposed in regular longitudinal lines ; the 

 hinge-line along the dorsal valvular commissure is slightly depressed, and there is likewise 

 a similar, though short depression on the ventral surface near the middle of the two 

 contact margins. The shell of the male (fig. 5, e-f) is altogether more slender, and 

 more tapered towards the hinder extremity. Length, l-43d of an inch ("57 mm.). 



Found only in anchor-mud, from a depth of 6 fathoms, in Stanley Harbour, Falkland 

 Islands. (Station 316.) 



This species I have much pleasure in naming after Mr H. N. Moseley, F.E.S., whose 

 admirable researches on the structure of Corals, and in other departments of Natural 

 History, especially in connection with the voyage of the Challenger, are too well known 

 to need recital here. Cythere moseleyi, in lateral view, and in style of sculpture, 

 resembles rather closely Cythere pellucida, Baird, to which species I was at first disposed 

 to refer it, but the posterior ventral angle in the latter species is rounded away entirely, 

 and the other aspects of the shell are also very much less angular than in Cythere 

 moseleyi. The male exhibits at the posterior angle some approach to the pelh(cida 

 character, and is altogether much more slender than the female, a condition which is 

 found to exist in most, if not all, members of the genus Cythere, and which is shown in 

 four of the species figured in PI. XU. — Cythere tenera, moseleyi, falklandi, and demissa. 



[PI. Xn. fig. 5, a-f. a Shell of female seen from left side, b from above, c from 

 below, d from front, e male seen from left side, / from below. All magnified 60 

 diameters.] 



6. Cythere falMandi, n. sp. (PI. XH. fig. 6, a-f). 



Carapace of the female rather tumid ; seen from the side, subquadrangTilar, higher in 

 front than behind, height equal to half the length ; anterior extremity well rounded ; 

 posterior truncated, rounded ofi" below, and excavated above the middle ; dorsal margin 

 slightly arched, highest in the middle ; ventral nearly straight ; seen from above, the 

 outline is ovate, twice as long as broad, mdest behind the middle, acuminate in front, 

 narrowed and truncated behind, lateral margins curved and somewhat sinuous ; end 

 view broadly ovate, width and height nearly equal, ventral border keeled. Surface of 

 the shell marked out into polygonal areolae, which are either slightly depressed or exca- 

 vated into distinct pits. Length, l-45th of an inch ('53 mm.). 



Found only in anchor-mud, from Stanley Harbour, Falkland Islands, depth 6 

 fathoms (Station 316). It is perhaps douljtful whether figures e and/ really belong to the 

 same species as a-d. 



(ZOOL. CHALL. EXP. PART III. 1880.) C 9 



