RECENT BRITISH OSTRACODA. 



435 



Of this species I have seen only one British specimen, a male, from which the figures 

 here given were taken. It seems to be very closely allied to L. itnpressa, as well as to 

 JO. tamarindus, and I should scarcely have ventured to describe it as a distinct species, 

 had its peculiarities not been carefully studied by G. O. Sars, and by him considered to 

 warrant its separation. The male has, as Sars observes, very much the same form as the 

 female of L. tamarindus ; but the shell-structure is much more like that of impressa, 

 which the female also resembles in outline. 



3. LoxocoNCHA ELLTPTiCA, n. sp, (Plate XXVII. figs. 38, 39, 45-48, and Plate XL. 



fig. 3.) 



Valves of the female, as seen from the side, subrhomboidal, rather higher in front than 

 oehind ; height equal to two-thirds of the length. Extremities obliquely rounded. 

 Superior margin arched ; inferior sinuated in front of the middle and slightly keeled 

 behind. Seen from above, the outline is oblong-ovate, extremities acuminate ; greatest 

 width behind the middle, equal to half the length. Lucid spots curved or comma-shaped ; 

 four placed transversely, with one or two at a little distance in front. Surface of the 

 shell smooth and finely punctate, bearing small scattered papillae, and often incrusted 

 like the preceding species. Colour yellowish brown, with patches of rather darker shade. 

 The male is larger, more elongated, and more regularly quadrilateral, the dorsal margin 

 nearly straight and angulated at its extremities ; seen from above the outline is more 

 compressed, the sides subparallel. Superior antennse slender; the second joint equal in 

 length to the two following ; last joint considerably longer than the preceding. Inferior 

 antennae scarcely different from those of the preceding species. Second joint of the 

 third pair of feet equal in length to the two following. 



Length (of the male) -^-q in., (female) ^5- in. 



Hab. In brackisli -water. Arnold^s Pool, Guernsey {Rev. A. M. Norman) ; Girdler Sand, Thames {Mr. 

 E. C. Davison) ; in pools at the mouth of the Seaton Burn and Wansbeck, Northumberland (G. S. B.). 



4. LoxocoNCHA TAMARINDUS (Jones.) (Plate XXV. figs. 45-48.) 

 Cytherideis tamarindus, Jones, Tertiary Entom. p. 49, pi. iii. fig. 4a, 4b. 



Cythere Icevata, Norman, Nat. Hist. Trans. Northumb. and Durh. vol. i. p. 18, pi. v. figs. 13-16, and Brit. 



Assoc. Report, 1864, p. 192. 

 Lowoconcha longipes, G. O. Sars, loc. cit. p. 63. 



British type. Distribution : Recent — Norway, Great Britain, Ireland, Bay of Biscay. Fossil — Crag, 

 England ; glacial and raised beaches, England, Scotland, Ireland, and Norway. 



Valves of the female, as seen from the side, oblong, subquadrilateral, equal in height 

 throughout ; length equal to nearly twice the height. Anterior margin evenly rounded ; 

 posterior angulated in the middle and obliquely truncate above. Inferior margin straight, 

 terminating behind in an obtuse angle ; ventral sinuated in front, slightly convex behind. 

 Outline, as seen from above, oblong-oval, greatest width in the middle, equal to less 

 than half the length ; extremities pointed. Shell fragile, pellucid, smooth and polished ; 

 marked with a few fine scattered puncta. Colour white or yellowish. " Upper antenna) 

 much more robust than in L. impressa, and beset partially with spiniform setae ; second 



3 N 2 



