RELATIONSHIPS OF THE AUSTRALIAN CAINOZOIC SYSTEM. 
up the Muddy Creek past Clifton, at a point marked “G” on the 
sketch map (Fig. 13) the Balcombian fossiliferous sandy clays appear 
a few inches above the bed of the creek, and show a dip to the east 
of 8 degrees. This is surmounted by 4 feet of polyzoal rock with 
rolled fragments, containing many fossils common alike to either 
Balcombian, Janjukian, or Kalimnan strata, as Arca (Barbatia) 
consutilis, Cucullaea corioensis, Chama lamellifera, Pecten sturtianus, 
Cardita delicatula, and Venus (Chione) propinqua (specimens small 
and approaching the Spring Creek form V. (Ch.) halli, as well as a 
tooth of Galeocerdo, a form which has not occurred lower than the 
Janjukian. There is no doubt that whilst the Grange Burn area 
was rapidly subsiding, and given over to clear water conditions, 
on this, the east side of Clifton, the Janjukian sea was shallow, 
and subjected to currents, whilst very little deposition took place. 
Above this 4-ft. bed of polyzoal rock follows the typical Kalimnan 
strata resting on a nodule bed, the latter containing typical fossils 
of that stage, as Glycimeris halli, and fully developed specimens of 
Venus (Chione) propinqua. 
F.—The Mallee (Victoria) and the Mount Gambier District, the 
Adelaide Plains, and the Eucla Basin (South Australia). 
The first two of the above localities, so far as their underground 
geology is concerned, are comprised within one area of deposition. In 
Janjukian times that which is now the Southern Ocean extended for 
some hundreds of miles inland, forming a great gulf—the Murray 
Gulf. This gulf was bounded on the west by the great paleeozoic 
axis of which the Mount Lofty Ranges forms a part. Its deposits 
form the rocks of the Mount Gambier district, and an extension of 
the area underlies the Adelaide Plains. The fossil fauna of the latter 
area, as exemplified in the polyzoal limestones of South Australia, is 
practically identical with the white limestone and marls of the lower 
portion of the borings in the Mallee of Victoria. The sediments 
laid down to the north of Gregory’s “ Primitive Mountain Chain ** 
formed the foundation of the vast area occupied at the present day 
by the basins of the Wimmera, Murray, Darling, Murrumbidgee, 
and Lachlan Rivers; and which form the great subartesian 
basin of the Murray Gulf. In New South Wales alone this sub- 
artesian area comprises, according to C. 8. Wilkinson, no less than 
22,000 square miles. 
These older deposits revealed by boring in the Mallee, Victoria, 
in South Australia and New South Wales, show, by their fossil 
contents, that they are Janjukian or Miocene in age. The only 
Cainozoic fossils found in the New South Wales bores occurred at 
Arumpo,f and one of them is strongly confirmatory of this conclusion 
* Gregory, J. W. Geography of Victoria, 2nd ed., 1912, p. 75. 
+ Ree. Geol. Surv. N.S. Wales, vol. iii., pt. 4, 1893, p. 115. 
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