LAMELLIBRANCHIATA. 61 



8. C. zealandica, Quoy, I.e., Hi., p. 511. Small ovato-trigonal, 

 swollen behind, finely longitudinally striated. Yellowish or pinkish 

 white, interior brownish, margin brown. Height, '3 ; length, '5 ; 

 breadth, '25. 



Common. Found also in Australia. 



* 9. C. CatlOWSB, Reeve. Shell oval, thick, rather depressed, 

 smooth, whitish rose or yellowish, posterior side rounded, anterior 

 slightly angular ; interior vivid rose colour. (Reeve.) 



* 10. C. adllSta, Hinds, Voy. Sulphur. Shell somewhat obliquely 

 triangular, smooth, rather swollen, rounded posteriorly, slightly angu- 

 lately accurninated anteriorly ; reddish brown, covered with a horny 

 epidermis; umbones eroded. (Reeve.) 



Rather stouter than the preceding, and less anteriorly accuminated. 



FAMILY ANATINIDJE. 



Interior nacreous, more or less gaping at the extremities ; ligament 

 external ; cartilage internal, placed in corresponding pits and furnished 

 with a free ossicle. 



ANATINA. 



Oblong, ventricose, very thin, often translucent, sub-equivalve, 

 umbones fissured, directed backwards ; hinge with a spoon-shaped 

 cartilage process in each valve ; pallial sinus wide and shallow. 



India. Philippines. Australia. "W. America. 



11. A. tasmanica, Reeve. Ovate, umbones sub-central, finely 

 longitudinally striated. Height, 2'5 ; length, 3 - 8. 



From Auckland as far south as Massacre Bay and Otaki. Australia. 



LYONSIA. 



Left valve slightly larger, thin ; cartilage plates oblique, covered by 

 an oblong ossicle ; pallial sinus angular ; interior sub-nacreous. 

 Europe. "West Indies. India. Philippines. Borneo. Peru. 



12. L. Vitrea, sp. nov. Elongately oblong, very thin, slightly 

 gaping and truncated behind ; umbones sub-central, smooth, white, 

 finely longitudinally striated ; pallial sinus extending to the centre of 

 the shell, rounded. Height, '5 ; length, '75. 



THRACIA. 



Oblong, slightly compressed, attenuated and gaping posteriorly ; 

 cartilage process thick, not prominent, with a crescentic ossicle ; pallial 

 sinus shallow. 



North Atlantic, from Greenland to the Canaries. China. Australia. 



* 13. T. noyae Zealandise, Reeve. Shell somewhat triangularly 

 ovate, rather solid, posteriorly rather broadly angled ; left valve flat ; 

 concentrically rudely plicately striated, especially towards the umbones ; 

 umbones rather sharp, a little beaked, whitish, smooth. (Reeve.) 



Possibly a variety of T. australica. 



