IMPEEFECTLT-KNOWN SPECIES OP OSTRACODA. 447 



long setae, which are crowded together on the last four joints; mandible slender and 

 feebly toothed (fig. 4) ; palp very long and slender, destitute of branchial rays, basal 

 joint bearing one extremely long and stout, falcate, plumose seta, and two much 

 shorter, simple setse; penultimate joint with two, last joint with three, small apical 

 setse. Length -88 mm. 



Hah. One specimen only in a dredging from Lyttelton Harbour, 1-5 fathoms. 



Family CYTHERELLID^ Sars. 



Genus Cytherblla Jones. 



Cytherella ebursea, sp. n. (Plate XL VI. figs. 8, 9.) 



Shell, seen from the side (fig. 8), subelliptical, about twice as long as high; 

 extremities well rounded, dorsal and ventral margins nearly straight. Seen from above 

 (fig. 9), the outline is club-shaped, widest near the posterior extremity, width equal to 

 more than one-third of the length ; anterior extremity very obtusely rounded, posterior 

 much wider, subtruncate, with rounded angles; lateral margins converging slightly 

 from behind to the anterior extremity. Surface of the valves quite smooth and 

 polished. Colour grey. Length -9 mm. 



Hah. Lyttelton Harbour, among weeds. One specimen only found. 



EXPLANATION OF THE PLATES. 



PLATE XLIII. 



Aster ope australis, p. 431. 



Fig. 1. Shell of male, seen from left side, 



Fig. 2. „ „ above, ^ ^ ^^ 



Fig. 3. Shell of female, seen from right side, | 



Fig. 4. „ » above, J 



Fig. 5. Inner branch of antenna, ^ A oiq 



Fig. 6. „ „ Z,\ 



Fi". 7. Process of mandibular foot, X 180. 



Fio-. 8. Post-abdominal lamina, X 180. 



Asterope grisea, p. 432. 



Fig. 9. Shell of female, seen from right side, | ^ ^5. 

 Fig. 10. „ „ above, J 



