REPORT ON THE OSTRACODA. 121 



extremities broad, mucronate ; end view broadly ovate, width nearly as great as the 

 height. Surface of the shell sculptured with deep and closely-set angular excavations, 

 which are usually fainter, and sometimes wanting altogether, in the centre of the valves. 

 Shell of the male (figures e-f) narrower and more compressed, the dorsal and ventral 

 margins nearly parallel. Lengtli, l-4.5th of an inch (-53 mm.). 



An extremely well-marked species, the range of which seems to be very restricted. 

 In the recent state it is known only as an inhabitant of the western shores of Europe 

 (Norway, the British Islands, France, and Spain), and as a fossil it occurs not uncom- 

 monly in the Post-Tertiary deposits of Britain and Norway. The specimens here figured 

 Avere found in anchor-mud from Vigo Bay. 



[PI. XXIX. fig. 1, a-f. a Carapace of female seen from left side, h from above, c 

 from below, d from front, e male seen from left side, f from above. Magnified 50 

 diameters.] 



10. Loxoconcha suhrhomhoidea, n. sp. (PI. XXVIII. fig. 4, a-d). 



Carapace short, and rather tumid ; seen from the side, subrhomboidal, equal in height 

 before and behind, height equal to two-thirds of the length ; extremities broad and 

 obliquely rounded, dorsal margin nearly straight, ventral slightly convex ; seen from 

 above, ovate, widest near the middle, scarcely twice as long as broad, extremities 

 rounded and mucronate ; end view subcordate, slightly tapered towards the apex. 

 Surface of the shell marked with angular excavations, as in the preceding species. 

 Length, 1-6 0th of an inch ('425 mm.). 



Dredged in Simon's Bay, South Africa, in a depth of 15 to 20 fathoms (Station 

 140). 



[PI. XXVIII. fig. 4, a-d. a Carapace seen from left side, h from above, c from 

 below, d from front. Magnified 50 diameters.] 



11. Loxoconcha variolata, G. S. Brady (PI. XXIX. fig. 6, a-d). 



Loxocmicha variolata, Brady, Ostracoda of Antwerp Crag, Trans. Zool. Soc, vol. x. pt. 8, 1878, 

 p. 400, pi. Ixviii. fig. 4, a-d. 



Carapace, as seen from the side, oblong, rather higher in front than behind ; height 

 equal to more than half the length, anterior extremity broad, and evenly rounded, 

 posterior narrower, rounded, not produced nor emarginate, dorsal margin straight, ventral 

 slightly convex ; seen from above, hastate, with parallel sides, which converge abruptly 

 to a mucronate apex in front, and terminate rectangularly behind the middle, thence 

 converging sharply backwards in a bisinuated line to the mucronate posterior termination ; 

 width equal to the height ; from below, the posterior lateral angulation is seen to be 

 carried across the ventral surface of the sheU, forming a sharp ridge ; viewed from the 



(zOOL. CHALL. EXP. — PART HI. 1880.) C 16 



