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deep water conditions, under which there probably ensued a large amount 
of disturbance by submarine currents. It is generally under such conditions 
that the richest fish faunas flourish, and such seems to have been the case 
in this Janjukian gulf at the place where the glauconitic marls were laid 
down. It is usual in these green-sand samples also, to find the group 
of the ostracoda thoroughly representative and abundant. Deep-water 
species of the ostracoda are typical in these green sands, as Cythere dictyon , 
which also occurs frequently in the white limestone or polyzoal rock of the 
later bores associated with other deep-water species as Cythere dasyderma , C . 
normani and C. scutigera. Having a distinctly glauconitic deposit we may reason¬ 
ably conclude that it was formed at greater depths than the ordinary mud-line 
of 100 fathoms. The large proportion of nodosarines amongst the foraminifera 
occurring in the green-sands would also point to their deep-water habitat. 
As a rule the polyzoal rock underlies the green-sand and marl in the old 
Murray Gulf, as revealed by the borings. At Torquay, conversely, this 
limestone forms the younger part of the series, overlying the blue and green 
glauconitic clays of the basal beds of Bird Rock. It is thereby seen that 
these two phases of sedimentation have sometimes been interchangeable 
in the Janjukian period according to local conditions ; the green-sands 
representing slow accumulations of living organisms, with much solution and 
intermittent accessions of terrigenous material to the deposits, whilst the 
polyzoal phase shows a clarity of water and an evenly subsiding sea-bed. 
The deeper parts of the borings, occurring as they do in polyzoal rock, show 
a sedimentation of fairly deep-water origin, probably of 100 to 300 fathoms 
or even more. 
The mollusca of the deepest parts of the Mallee bore No. 11 are mainly 
represented by the genera Pecten and Spondylus ; the brachiopods by Tere - 
bratulina, Magellania and Magasella ; and the corals by Bathyactis and some 
Alcyonarians. A deposit having a similar fauna was met with in the Gulf 
of Lyons at about 265 fathoms. The trawler Endeavour has lately dredged 
up some similar material from the Southern Ocean, 40 miles south of Cape 
Wiles, South Australia, at 100 fathoms. In appearance this dredging was 
extremely like the fine white polyzoal limestone of the deeper part of the 
Mallee bores, excepting for its pale-yellowish colour, due to the presence of 
organic matter. There was practically no clayey material to wash away in 
order to facilitate the examination of its organic contents, and only a fine 
residue of 0 • 4 per cent, of sharp white quartz sand. The bulk of the material 
consisted of polyzoa and foraminifera, whilst ostracods were fairly common, 
and alcyonarian joints also present. Of the ostracods in this Southern 
Ocean deposit the following ten species were common to this and the Mallee 
fossil deposits of the Janjukian (Miocene) :— 
* Macrocypris decora, G. S. Brady sp. 
Bairdia amygdaloides, G. S. B. 
Cythere canaliculata, Reuss. sp. 
,, crispata, G. S. B. 
,, dictyon, G. S. B. 
,, lepralioides, G. S. B. 
,, parallelogramma , G. S. B. 
,, scabrocuneata , G. S. B. 
Loxoconcha australis, G. S. B. 
Xestoleberis variegata, G. S. B. 
The Janjukian series, as revealed in the borings, is sometimes followed 
by a mixture of Janjukian and Kalimnan faunas, at others immediately by 
the Kalimnan. Some of the bores have not penetrated beyond the Kalimnan, 
as bore 7. 
