LAMELLIB RANCHIATA. 



NEJERA. 



Thin, transparent, generally prolonged into a gaping beak behind 5 

 hiuge with a small spoon-shaped process in each valve, and a large 

 lateral recurved tooth in the right valve. 



Europe. China. Moluccas. Chili. Australia. 



14. N. trailli, sp. nov. Ovate, produced behind, white, with 

 distant concentric laminae, which become obsolete on the beak ; beak 

 rugose. Height, - 2 ; length, "4. 



Stewart's Island, 14 fathoms. 



MYODORA. 



Trigonal, rounded in front, attenuated and truncated behind ; right 

 valve convex, left flat ; interior pearly ; cartilage narrow, triangular, 

 between two tooth-like ridges in the left valve, with a free sickle-shaped 

 ossicle ; pallial line sinuated. 



Australia. Philippines. 



15. M. Striata, Quo//, I.e., iu., p. 537. Ovato-trigonal, solid, 

 longitudinally striated, anterior end rounded, posterior sub-augulated 

 and folded; sub-equilateral, apex acute. White; interior pearly. 

 Height, 1-3 ; length, T55. 



Common. 



The Natives call this shell " pakira." 



16. M. OVata, Reeve. Small, oblongo-trigonal, distantly longi- 

 tudinally plicated, anterior end rounded, posterior sub-angulated and 

 slightly folded ; sub-equilateral, apex acute. Yellowish or pinkish 

 Avhite ; interior pearly. Height, '6 ; length, "45. 



Stewart's Island. Australia. Philippines. 



17. M. "brevis, Stutchlury, Zool. Jour., v., p. 99. Small, thin, 

 trigonal, nearly as high as long, distantly longitudinally plicated ; sub- 

 angulated at both ends ; sub-equilateral, apex acute. White ; pearly 

 inside. Height, '35 ; length, '4. 



Stewart's Island, 14 fathoms. Australia. 



CHAMOSTRJEA. 



Inequivalve, solid, attached by the right valve ; left valve flat. 

 Australia. 



18. C. albida, Lamark, vi., p. 585. Eight valve keeled, attached 

 by its anterior side ; umbones anterior, sub-spiral ; left valve with an 

 oblong curved ossicle. Length, 2'5. 



Manukau ; Kawhia ; Cook Strait. Chatham Islands. Australia. 



ORDER VENERACEA. 



Animal with two siphons, more or less elongated, and often divided ; 

 foot generally compressed, formed for creeping or jumping. 



FAMILY MACTRID^;. 



Equivalve, trigonal, close, or slightly gaping ; ligament triangular, 

 internal, in a deep triangular pit ; epidermis thick ; hinge with two 



