374 



1893. Chione cainozoica, Tate and Dennant, Trans. Eoy. Soc. South Aust. 

 vol. xvii. pt. 1, p. 225. 



1895. Chione cainozoica, Tate and Dennant, id. vol. xix. pt. 1, p. 113. 



1896. Chione cainozoica, Pritchard, Proc. Eoy. Soc. Vict. vol. viii. n.s. 



p. 135. 



Shell suborbicular, highly convex; surface with thin erect 

 concentric lamellae, which are much more closely-set than any 

 other Australian Eocene Chione hitherto described ; lunule broadly 

 heart-shaped, defined by a groove which interrupts the regular 

 course of the concentric lamellae. 



Dimensiotis. — Height 18 mm. ; length 20 mm. 



Form, and Zoo. — Eocene : Victoria and South Australia. 



L. 9888. Examples of dilFerent stages of growth ; from Muddy 

 Creek. Purchased. 



L. 10587. Eight valve, much crushed, probably referable to this 

 species ; from Willunga. IT. Y. L. Brown Coll. 



Chione subroborata, Tate. 



1887. Chione subroborata, Tate, Trans. Eoy. Soc. South Aust. vol. ix. p. 156, 

 pi. xiv. fig. 17. 



Shell cordately trigonal, solid, broader anteriorly than posteriorly, 

 Timbones flattened, well forward; readily distinguished from 

 C. cainozoica not only by its shape, but by the surface concentric 

 lamellae, which are very solid and distant from each other, there 

 being only fifteen or sixteen on each valve in the adult; lunule 

 small ; pallial line some distance from the ventral margin. 



The author compares it with the living C. rohorata, Hanley. 



Dimensions. — Height 22'5 mm. ; length 25-5 mm. 



Form, and Loc. — Miocene : Victoria. 



L. 355. Dwarfed specimens, a local variation of this species (?) 

 from Bairnsdale. Presented by W. H. Grigson, JEsq. 



L. 4830. Both valves ; from Muddy Creek. 



Presented hy John Dennant, Esq. 



L. 6605, L. 9884. Donble-valved specimen, and separate right 

 and left valves of the adult; from Muddy Creek. Purchased. 



