The next stage, the Werrikooian (Upper Pliocene), contains a large percentage of living species, as Ostrea angasi, Placunanomia ione (ranging down into Janjukian), Glycimeris radians, Leda crassa (also a common Kalimnan fossil), various species of Venus (Chione), as V. strigosa and V. placida, and Barnea australasiae.
Pleistocene Bivalves.—
The bivalved shells of the Pleistocene are similar to those now found living round the Australian coast, as Pecten asperrimus, Mytilus latus, Leda crassa, Soletellina biradiata and Spisula parva.
Pleistocene shells of bivalved genera occur in the coastal hills of Papua, including the following:—Cultellus, Corbula, Mactra, Tellina, Venus (Chione), Dione, Dosinea, Leda and Arca.
The SCAPHOPODS (“digger foot”) or the “Elephant-tusk shells” are adapted, by their well-developed foot, to burrow into the mud and sand.
Fig. 97—FOSSIL SCAPHOPODS and CHITONS.
A—Dentalium huttoni, Bather. Jurassic. New Zealand
B—Dentalium mantelli, Zittel. Cainozoic. Victoria
C—Chelodes calceoloides, Eth. fil. Silurian. New South Wales
D—Ischnochiton granulosus, Ashby and Torr sp. Cainozoic (Balc). Victoria
E—Cryptoplax pritchardi, Hall. Cainozoic (Kalimnan). Victoria