IMPBKFECTLT-KNOWN SPECIES OF OSTRACODA. 433 



Frontal tentacle (fig. 27) three-jointed, the median joint very short and constricted at 

 the base, distal joint conical, with a much-attenuated apex ; secondary branch of the 

 antenna (fig. 26) three-jointed, cylindrical, ending in a long seta, the two basal joints 

 bearing a few marginal hairs; teeth of the bifid extremity of the vermiform limb 

 (fig. 28) corrugated, their apices formed by a small spine, which is overhung by a 

 knobbed columnar process : abdomen fringed distally with closely-set hairs ; post- 

 abdominal laminae (fig. 29) bearing three very stout, blunt, and strongly curved distal 

 ungues, which bear two marginal rows of closely-set lancet-shaped spinules (fig. 30) ; 

 in front of the ungues is a series of about nine long ringed and pinnated setae. Male 

 unknown. 



Hah. Eock-pools, Stewart Island. 



This fine species closely resembles in external aspect C. orbicularis, of which a 

 single specimen from Valparaiso was described by me [loc. cit.), but G. ovulum is much 

 larger, and differs in many points as regards the soft parts. 



Ctclastbrope teneka, sp. n. (Plate XLIV. figs. 27-29.) 



Female. Shell, seen from the side (fig. 27), almost circular, slightly narrower towards 

 the front, length about one-seventh greater than the height, very thin, membranous, 

 and slightly wrinkled ; anterior and inferior margins beset with distant, rigid hairs. 

 Secondary antennal branch (fig. 28) simple, three-jointed, with a long apical seta; 

 falcate process of the mandible bearing numerous marginal spines and teeth ; 

 the post-abdominal claws are three in number (fig. 29), very unequal in length, and 

 armed with closely-set short marginal spinules. Length 1"5 mm. 



Hah. Lyttelton Harbour, 1-5 fathoms. One specimen only. 



CrcLASTEROPE ZBALANDiCA (Baird). (Plate XLllI. figs. 15-23.) 

 Cypridina zealandica Baird (i), p. 257, pi. xvii. figs. 11-13. 



Shell of the female (figs. 15, 16), seen from the side, very broadly ovate, length 

 about one-fourth greater than the height, the outline forming a perfect oval except at 

 the antennal notch, which is small and shallow ; seen from above, ovate, compressed, 

 greatest width in the middle, and equal to half the length ; extremities rather wide and 

 evenly rounded, slightly emarginate at the contact of the valves. Shell calcareous, 

 finely punctate and, towards the anterior extremity, faintly wrinkled in a transverse 

 direction (fig. 23). Length 5 mm., height 4 mm. Secondary branch of the antenna 

 (fig. 19) cylindrical, three-jointed, geniculated, the first joint bearing a tuft of marginal 

 set® near its extremity, second joint witli three small marginal setse externally and a 

 lono- seta on its internal distal angle, last joint obliquely truncate and mucronate at 

 its apex ; ungues of the post-abdominal laminae (fig. 21) stout, subequal, and strongly 



