1006 PELECYPODA. \Eulamellibranchda. 



ment short, strong, much raised externally. Adductor-scars unequal, 

 the anterior oblong, the posterior irregularly rounded. Pallial sinus 

 long, horizontal, coalescent with the pallial line, narrowly rounded 

 in front. 



Length, 50mm. ; height, 26mm. (type). Length, 42mm. ; height, 

 22 mm. ; diameter, 7-5 mm. 



Type in the British Museum. 



Hob. Throughout New Zealand, in 2 to 5 fathoms, in sandv 



^/ 



bottom. Kermadec Islands (Captain Bollons.) 

 Fossil. Miocene and Pliocene. 



2. Soletellina siliqua, Reeve, 1857. Plate 62, fig. 12. 



Soletellina siliqua, Reeve, Conch. Icon., x, 1857, f. 10 ; Grit. List, 42 ; 

 M.N.Z.M., 142. Solenotellina siliqua, Reeve, Index, 89. Hiatula siliqttce, 

 Hart., C.M.M., 66. H. siliqua, Reeve : Button, P.L.S. N.S.W., ix, 520. 

 Solenotellina nitens, Tryon, Arner. Journ. Conch., v, 1870, 171, pi. 16, 

 f. 9 ; C.M.M., 66 ; M.N.Z.M., 143. 



Shell oblong, transverse, thin, inequilateral, shining, yellowish- 

 brown, obliquely truncated and subangled behind, with fine growth- 

 lines. Beaks small, not raised. Anterior end usually slightly longer, 

 rounded, the dorsal margin straight, but slowly descending ; posterior 

 end obliquely truncated, narrowly rounded or angled towards the 

 ventral margin, dorsal margin convex, rather rapidly descending ; 

 ventral margin broadly rounded. Sculpture consisting of very fine 

 growth-lines and distant fine radial scratches. Epidermis thin, horny, 

 shining. Colour yellowish and greenish-brown, with concentric bands 

 of lighter and 2 obscure posterior rays. Interior bluish or purplish- 

 white. Margins thin, smooth, sharp, the epidermis extending a little 

 beyond them. Hinge very narrow, with strong nymphs ; right valve 

 with 2 cardinals, sometimes a third rudimentary posterior tooth is 

 present ; left valve with 2 diverging cardinals, the anterior triangular, 

 the posterior thin and rather long. Ligament strong, short, external, 

 and much raised. Adductor-scars unequal, the anterior smaller, 

 elongate, the posterior roundish. Pallial sinus large and deep, extend- 

 ing to the anterior third of the length of the valves, descending and 

 angular in front, coalescent below with the pallial line. 



Length, 45 mm. ; height, 23 mm. ; diameter, 10 mm. 



Type in the British Museum. 



Hob. New Zealand (Hart, Strange, Dr. T. B. Wilson). Auck- 

 land Harbour ; Lyttelton Harbour, in 2-4 fathoms ; Akaroa Harbour 

 (H. S.) ; Preservation Inlet. 



Remark. On examining specimens from different localities 1 

 found it impossible to separate the several species which were chierlv 

 based on the more rounded or slightly rostrate posterior end. All 

 intermediate forms occur, but the sculpture, the hinge, and the pal- 

 lial sinus are similar in all forms. 



