CUCULL^A. 337 



the teeth arc very small and vertical in the centre, antl large and 

 horizontal at the extremities of the hinge-line ; margin of the 

 valves crenulated. The surface ornament consists of numerous, 

 closely-set, radial ribs and lineations, crossed by transverse lines 

 and ridges of growth. 



Dimensions. — Height 49 mm. ; length 63 mm. 



Form, and Loc. — Eocene : Tasmania, Victoria, and South 

 Australia. 



42684. Cast of an adult ; (locality ?) South Australia. 



Presented by the Governors of Adelaide Museum. 

 42698. Cast of a left valve ; from near Adelaide. 



Presented hy M. Marshall, Esq. 



70399. Cast of both valves, in ferruginous sandstone; from 

 Mordialloc, near Melbourne. Purchased. 



70411. Double - valved specimen; from " Meribee river," 

 Victoria. Purchased. 



83978. Right valve, neanic stage of growth ; from Table Cape. 



Purchased. 

 98219. Left valve of an adult ; from Flinders I. Purchased. 



L. 4789. Examples of the neanic and ephebic stages of growth, 

 both valves ; from Muddy Creek. Presented by John Dennant, Esq. 



L. 5644. Cast of both valves ; from Gippsland. 



Presented hy the Rev. J. S. H. Royce. 



L. 6598. Eight and left valves, in which the ventral margin 

 is strongly plicated in the interior ; from Muddy Creek. Purchased. 



L. 9835. Series illustrating stages of growth, from the brephic 

 to the ephebic. The smaller specimens indicate that at an early 

 stage the interior of the shell is radially lineated, whilst the 

 external ornament is very pronounced. From Muddy Creek. 



Purchased. 



L. 10568. Specimens of both valves ; from Uivor ^furray cliffs, 

 near Adelaide. Presented by Wm. Evans, Esq. 



L. 10571. Cast of a rather elongate variation ; from Hiver 

 Murray cliffs. Transferred from the Museum of Practical Geology. 



L. 10572. Casts of left valves ; from the Tertiary of Fowler's 

 Bay District. H. Y. L. Brown Coll. 



z 



