
SOME TERTIARY FOSSIL MOLLUSCS 
FROM THE 
ADELAIDEAN STAGE (PLIOCENE) or SOUTH AUSTRALIA 
By BERNARD C. COTTON, Concrotocist, Sour AusrratiAN Museum, 
Plates xx—xxli. 
INTRODUCTION. 
Wuitez working out the macrofauna of numerous water bores sunk in the Adelaide 
Plains by the Mines Department, for agricultural purposes and to provide water 
for pumping into the mains, a number of interesting molluses were discovered, 
A few of these are described here; also some Abattoirs bore specimens selected by 
Sir Joseph Vereo and myself from material donated to the South Australian 
Museum by H. §, Pratt in 1925, The latter specimens bear the inclusive 
registration number P, 173, A few also ave described from the Salisbury Bore, 
330 feet, from samples in the Tate Museum at the University of Adelaide. 
Recent examination of material from the uppermost oyster beds at Mannum, 
Swan Reach and some other places along the River Murray cliffs, proves a similar 
suite of fossils to be present, with the dominant QOstrea arenicola and also 
O, sturtiana. These uppermost beds of the Murray Cliffs are probably exposures 
of the Adelaidean stage. From deep building excavations in the central ity area, 
samples of the Adelaidean stage have been obtained. A rich bed of this deposit 
was found in the seepage well at the base of the Bank of New South Wales, King 
William Street, excavations at about 50 feet. A sample from there was found in 
the Mines Department. It contains the following typical Adelaidean fossils: 
Mimachlamys antiaustralis, Equichlamys consobrinus, Equichlamys subbifrons, 
Spondylus spondyloides, Ostrea wrenicola, Veletucela subradians, Neodiastoma 
provist. 
Samples from the samie and other localities are in the South Australian 
Museum, Apparently this is a similar bed to that mentioned by Tate, 1883, in 
the Kent Town Bore ‘‘Series a’’ in which he records ‘‘oysters and pectens’’ as 
dominant. Incidentally, Zyuichlamys consobrinus and B. subbifrans both of Tate 
1885, seem to be synonymous, Z, consobrinus having priority, Z. subbrifrons being 
probably a juvenile. This Adelaidean deposit of fossils forms the principal porous 
bed in which the water of the aquifer is contained under the Adelaide Plains. 
