ASTARTE. 



125 



or pitchy; concentric waves not numerous (a1iout twenty), large 

 except on the beaks, recurved, and often quite wanting- near the ven- 

 tral margin, and along the posterior slope ; this absence of folds is 



435. 



A. elUptica. 



A. illijitica. 



often quite remarkable, even in young shells. Fine concentric lines 

 are generally found on lioth ribs and interspaces. The hinge-mar- 

 gin is quite narrow and delicate, as the beaks do not 

 rise to a point so as to form a large triangular area for 

 the hinge, and the teeth are by no means conspicuous 

 and robust; color of interior a dead livid or leaden 

 color ; muscular and pallial impressions large and 

 deep ; inner margin always simple. 



The elongated, elliptical form, usual disappearance of waves near 

 the ventral margin and rear, delicate hinge and hinge-margin, 

 dingy-white or livid interior, and simple inner margin at the most 

 antiquated stages, are quite enough to determine the specific value 

 of this shell. 



Astarte Banksii. 



Shell small, elevated, heart-shaped, tumid ; beaks acute, anterior margin exca- 

 vated, lunule deep and broad, surface with crowded, well-defined waves, inner 

 margin smooth. 



Astarte Bunlsii, Leach, in Ross's Voy. Appendix. — Gray, Zool. Bcechcy's Voy. pi. 44, 

 fig. 10. — SowERBY, Thes. Conch, ii. 782, pi. 167, fig. 8. 



Shell quite small, ovate-triangular or oliliquely heart-shaped, tu- 

 mid ; beaks nearly median, prominent, acute, pointing 

 forwards, the lunule broad and deeply excavated ; an- 

 terior dorsal slope concave, sometimes remarkably so, 

 rendering the anterior portion much less elevated and 

 smaller than the posterior, and forming an angle as it 

 joins the well-rounded end, which curve passes into 

 that of the gently curved base ; posterior dorsal margin 

 always very slightly swelling, though nearly direct, but rapidly de- 



Fig. 438. 



A. Banksii. 



