Ostracod and Shell Marl of Pleistocene Age. 31 



N.W. corner of Tasmania passing northwards to the east of King 

 Island, and joining with the Cape Schanck area.^o 



That there is a slight antiquity to be ascribed to the Boneo 

 deposit seems to be shown by the presence of marine shells, for the 

 existing conditions would appear to preclude their penetration so 

 far inland, unless perhaps by an abnormally high tide. No doubt 

 the actual conditions at the time of deposition were those of tidal 

 -swamps, such as may be seen in the coastal lakes of the Ninety 

 Mile Beach in Gippsland. 



This marl is not phosphatic, as might be supposed from the 

 abundant remains of ostracoda. An explanation of this may 

 be found in the fact that those forms wdiich do occur are all thin- 

 shelled, and of the more purely calcareous type of freshwater 

 -genera. 



The organic remains found in this marl are : — 

 Pelecypoda. Erycijia helmsi, Hedley. 

 Gasteropoda. Coxiella sfn'afula, Menke sp. 



Bidlinus ociitispira, Tryon sp. 

 Ostracoda. Cypris mytiloides, G. S. Brady. 

 ,, %ydneia. King. 

 ,, temiisculpfa, sp. nov. 

 Candonocypris assdmile, G. 0. Sars. 

 Cythere luhhochiana, G. S. Brady. 

 Limnicy there sicula, sp. nov. 



EXPLANATION OF PLATES. 



Plate IIL 



Fig. 1. — Erycvna helmsi, Hedley. Left valve. x 10. 



,, 2.— £'. helmsi, Hedley. Interior of left valve of another 



specimen, x 10. 

 ,, 3. — Coxiella striatula, Menke sp. 

 ,, 4. — Bidlinus acutispira, Tryon sp. x 5. 

 ,, 5. — Cypris mytiloides. G. S. Brady. Right valve. 5o, ven- 

 tral edo-e view of the same, x 26. 



10. In Dr. F. Noetling's paper on the Antiquity of Man in Tasmania (Proc. 

 R. Soc, Tasmania, 1910), that author, on plate I., Fig. 6, shows the 

 Tasmania- Victorian coastal contours, as would appear from an uplift 

 of 40 fathoms of the present sea bottom in the Strait. The tongue of 

 land thus brought up -w'ould form a direct connection froi-n the Smithton 

 (N.W. Tasmania) district to the Boneo (Cape Schanck) locality, and 

 this view helps considerably to explain the theory here advanced, that 

 the Boneo fluviatile faima was, in part at least, derived from a Tas- 

 manian one. 



