207 



Male of somewhat larger size than female and slightly differing in the 

 shape of the shell, the posterior part of which is greatly swollen. Copulative 

 appendages very large, with the basal part rounded quadrangular in shape 

 and sending off below, at the junction with the terminal part, a slender pos- 

 teriorly-curving piece sligtly sigmoid at the end, copulatory string comparatively 

 short; terminal part somewhat securiform in shape, being exerted at the 

 posterior corner to a narrowly rounded lobule. 



Colour of shell not yet ascertained. 



Length of adult female 0.57 mm., of male 0.61 mm. 



Remarks. The. male specimen figured by Brady & Norman in 1889 

 under the name of C. cornuta Brady seems to agree pretty well with the 

 male of the present species, as here described. I think however that its identifi- 

 cation with the form originally described by Brady under that name is wrong. 

 In any case the specific name cornuta is quite unapplicable to the present 

 species, as there is no trace of any corniform lateral projection, either in the 

 female or in the male. The form recorded by Brady in his Monograph as 

 C. Gibba O. Fr. Miiller is unquestionably the female of the present species. 



Occurrence. Two specimens only (a male and a female) of this form 

 have as yet corne under my notice. They were found among some Ostracoda 

 collected, some years ago, at Riser, south coast of Norway, from depths ranging 

 from 10 to 30 fathoms. 



Distribution. - British Isles. 



104. Cytherura affinis, G. O. Sars. 



(PI. XCVI, fig. 2). 

 Cytherura affinis, G. O. Sars, Oversigt af Norges marine Ostracoder, p. 77. 



Specific Characters. Female. Shell rather tumid, seen laterally, oblong 

 oval in shape, somewhat higher in front than behind, greatest height not 

 nearly attaining half the length, dorsal margin forming a quite even and gentle 

 curve throughout, without any indication of angle in the ocular region, ventral 

 margin almost straight in the middle and gently bowed behind, anterior 

 extremity broadly rounded, posterior produced to a rather prominent pro- 

 tuberance located slightly above the longitudinal axis of the shell; seen 

 dorsally, of a shape somewhat resembling that of the preceding species, but com- 

 paratively less broad, the greatest width scarcely exceeding half the length. 

 Valves with the central thickened area considerably reduced in extent, surface 

 conspicuously reticulated. Both pairs of antennse very slender and narrow, 



