A Synopsis of the Recent British Ostracoda. 125 



bearing a small lobe, from which spring two large and two 

 small setas. Abdomen ending in a very long acuminate pro- 

 cess; post-abdominal lobes narrow, bearing three hairs. 

 Valves unequal, smooth, or sparingly sculptured. 



B. simplex (Norman) ; turgida, Gr. 0. Sars. — It would not 

 be supposed, from the external appearance of these two spe- 

 cies, that they ought to be referred to one and the same genus ; 

 their anatomical characters, however, seem to agree closely. 

 The former is a much elongated species, acutely pointed at the 

 posterior extremity; the latter very tumid, subtruncate be- 

 hind, and much resembling, in general contour, the preceding 

 genus : it is pretty generally distributed, while B. simplex 

 appears to be confined to Scotland and the northern part of 

 England. B. simplex approaches a form described by Pro- 

 fessor T. Rupert Jones from fossil specimens under the name 

 Bairdia Harrisiana. 



Pseudocythere, Gr. 0. Sars. — Upper antennae seven- 

 jointed, bearing long setae ; second joint thick and armed 

 with a single seta in front ; last joint long and narrow, termi- 

 nated by very long setae : lower antennae very slender. Man- 

 dibles small and weak. Three lowermost setae of branchial 

 plate of first maxilla deflexed. Feet very long and slender. 

 Abdomen ending in a long slender process. No eye. Shell 

 thin and pellucid, rounded in front, produced at the postero- 

 dorsal angle. 



P. caudata, Gr. 0. Sars. — This genus contains only one 

 species, which is a very remarkable one, and apparently un- 

 common. The shell is sub quadrangular in outline, and so 

 much compressed as to appear almost squamous at the poste- 

 rior ventral extremity, where it is once or twice minutely 

 toothed. Colour brown, owing to the transparency of the 

 shell, through which the animal itself is seen. Its range is 

 extensive ; the few British specimens yet taken are from Con- 

 nemara, Northumberland, Shetland, and the Channel Islands. 



Cytherideis, Jones. — Carapace as seen from the side, 

 much attenuated in front, highest behind. Hinge margins 

 nearly simple : right valve overlapping the left in the middle 

 of the ventral surface. Animal unknown. 



G. subulata, Brady. 



The name Cytherideis was proposed by Professor T. 

 Rupert Jones, for a group of species which agreed in present- 

 ing a peculiar hinge structure, the margin of one valve pro- 

 jecting in a sort of angular crest, the other being cut away, so 

 as to receive it. The genus was not in any case very definite 

 in its characters, and its members must now be looked upon as 

 distributed amongst several other genera; but the species 

 above-named (G. subulata) cannot at present, from want of 



