1004; PELECYPODA. \Eulamdlibranchia. 



Sculpture consisting of unequal and fine concentric striae, crossed by 

 minute and dense radial lines. Epidermis thick, dark brown, mostly 

 worn off. Colour whitish or purplish-white, with numerous unequally 

 distributed radial rays of purple, interrupted by concentric whitish 

 bands. Interior purplish-white, the radial rays of purple marked 

 and very distinct at the ventral margins, the part between the scars 

 and the pallial impressions prominently callous, with 2 anterior and 

 1 posterior radial rays of shell-substance. Margins smooth, blunt. 

 Hinge with strong nymphs ; right valve with 2, sometimes only 1, 

 erect bifid teeth ; left valve with 1 bifid cardinal. Ligament external, 

 short, and very high. Adductor -scars unequal, impressed, the anterior 

 pyriform, the posterior roundish, larger. Pallial sinus large and 

 deep, linguiform, the posterior lower part coalescent with the pallial 

 line, extending beyond the vertical of the beaks. 



Length, 55mm. ; height, 33 mm. ; diameter, 18 mm. 



Type in the British Museum. 



Hob. Throughout New Zealand ; in sandy and muddy bottom, 

 below low-water mark. 



Maori. Wahawaha (testc Hutton). 



Fossil. Miocene and Pliocene. 



3. Psammobia zelandica, Deshayes, 1855. Plate 62, fig. 10. 



Psammobia zelandica, Desh., P.Z.S., 1854 (1855), 319 ; Crit. List, 42 ; Hutton, 

 J. de Conch., xxvi, 47 ; M.N.Z.M., 142 ; Bertin, Nouv. Arch. (2), iii, 

 1880, 119, pi. 5, f. 5. P. neozelanica, Desh. : Hutton, P.L.S. N.S.W., ix, 

 520. P. zonalis, Lamarck (?) : Hutton, C.M.M., 66 ; not of Lamarck. 



Shell rather small, oblong, thin, subequilateral, slightly ventricose, 

 sharply concentrically striated, whitish with radial rays of red. 

 Beaks not prominent, small, pointed, incurved. Anterior end some- 

 times very little shorter, narrowly rounded above, the dorsal margin 

 lightly convex and slowly descending ; posterior end rounded or 

 obliquely truncate, the dorsal margin straight or faintly concave ; 

 basal margin broadly rounded. Posterior dorsal area marked by a 

 faint ridge descending from the beaks to the lower posterior end. 

 Sculpture consisting of fine and sharp concentric strife, deeper and 

 waved on the posterior dorsal end, and crossed by very fine radial 

 stria?. Colour white or light orange with interrupted rays of purplish- 

 red descending from the beaks. Interior white or reddish-purple, 

 polished, showing the radial rays distinctly towards the margins. 

 Margins smooth. Hinge with short, strong nymphs ; right valve 

 with 2 diverging grooved cardinals ; left valve with 1 vertical 

 bifid cardinal. Ligament short, strong. Adductor - scars unequal, 

 impressed, the anterior pyriform, the posterior roundish. Pallial 

 sinus large, deep and broad, extending a little beyond the middle, 

 broadly rounded in front, and for the greater part coalescing with the 

 pallial line below. 



