372 



Genus SUNETTA, Link. 



[Besch. Rostock, Abth. iii. 1807, p. 148.] 

 Meroe, Sclmmacher, Essai Nouv. Syst. Habit. Testaces, 1817, p. 149. 



Shell oval, trigonal, depressed, almost equilateral ; posterior 

 margin much shorter than the amterior; readily distinguished from 

 Meretrix by the phenomena of the hinge, the position of the 

 umbones, and by the sinus. 



Type. — Chama sunet, Adanson. 



Sunetta gibberula, Tate (sp.). 



1887. Meroe gihberula, Tate, Trans. Eoy. See, South Aust. vol. is. p. 162, 

 pi. XV. figs. 4a-J. 



Posterior lateral area of the hinge large, broad, slightly convex ; 

 umbones acute ; margin crenulated ; surface smooth, shining, with 

 inconspicuous lineations and undulating growth-lines, which are 

 mostly developed near the ventral margin in the adult. 



Dimensions. — Height 24 mm. ; length 29 mm. 



Form, and Log. — Miocene : Muddy Creek, Victoria. 



L. 4824. Examples of both valves. 



Presented hy John Dennant, JEsq. 



L. 6610. Both valves of the adult. Purchased. 



L. 9870. Specimens of the neanic stage of growth. Purchased. 



Genus CHIONE, Megerle von Miihlfeldt. 

 [Ges. Naturf. Fr. Berlin, Magazin, 1811, p. 51.] 



Shell oval, triangular, cardinal border narrow, having on each 

 valve three divergent cardinal teeth, and, sometimes, on the left 

 valve a rudimentary anterior lateral tooth ; pallial sinus short, 

 triangular, or obsolete; surface of the valves lamellose, cancellated, 

 striated, or smooth. 



Type. — Venus dysera, Linnaeus. 



