374 TRANSACTIONS OF SECTION C. 
associated with the Balcombian of Muddy Creek. The polyzoal limestone of 
Muddy Creek rests on quartz porphyry, and is the basal member of the series. 
It has been traced by Dr, Pritchard and myself passing under the more loosely 
compacted beds of the district, and is inseparable from them. 
The polyzoal limestones of Jan Juc, Waurn Ponds, and a few other places 
are Janjukian, and the evidence rests on the mollusca, but this has no bearing 
on Mr. Chapman’s main contention. 
The relative age of the Janjukian and Balcombian is a difficult question. 
M‘Coy, Tate and Dennant, and Chapman consider the Janjukian the younger. 
Dr. Pritchard and myself consider the reverse to be the case. 
As regards the other formations, it may be briefly said that the estimate of 
their age depends on that of the Barwonian. If this be Eocene, they are 
Miocene and Pliocene respectively; if not, they must be placed higher in the 
scale, 
8. On the Age and Sequence of the Victorian Tertiaries. 
By G. B. Prircuarp, D.Sc. 
Tertiary geology in South-Eastern Australia has been fruitful of much 
difference of opinion, partly on account of lithological variations associated with 
paleontological variations which have not always received due weight, the diffi- 
culty of correlating disconnected outcrops, bores, and shafts, and the degree of 
antiquity and relative age of the various horizons represented. The various 
changes in this work have no doubt been a stimulation to some, but to many it 
has been, and still is, very confusing. 
It happens that marine deposits are well developed, many showing a remark- 
able wealth of fossils, and these have attracted more attention than their terres- 
trial and volcanic associates. Amongst the marine fossils, mollusca are usually 
very striking, and it is only natural to compare these with Australian living 
forms. In this way a succession can be determined for the fossil faunas as at 
present known, showing further and further removes from the living. 
(a) Werrikooian.—The type locality is at Limestone Creek, a small tributary 
of the Glenelg River, in the parish of Werrikoo, South-Western Victoria. 
These beds bear a molluscan fauna strictly comparable with living forms along 
the southern coast except for the occurrence of a few species at present unknown 
amongst the living fauna. 
(0) Kalimnan.—The type locality is near the township of Kalimna, Gipps- 
land Lakes, Eastern Victoria. The fauna of these beds is also comparable in 
general facies with the recent, in the proportion of bivalves to univalves, and 
relative abundance of representatives of other groups. It includes extinct 
genera, as well as a very high proportion of extinct species. 
(c) Balcombian.—The type locality is at Balcombe’s Bay, east shore of Port 
Phillip. The fauna of these beds is richer and more varied than the existing 
Southern fauna; its general facies is more comparable with Northern Australian 
forms. In the present state of our knowledge it contains rather more than two 
per cent. of extinct genera, and even allowing a wide margin for differences of 
opinion the living species would barely represent two per cent. 
(d) Janjukian.—Coastal sections on Bass Strait, parish of Jan Juc, south of 
Geelong. The fauna from these beds appears to be furthest removed from the 
living, based on a review of the genera which shows between five and six per 
cent. extinct, whilst the species only show about one per cent. living forms. 
When the typical fossils are not obtainable it is not easy to state whether a 
rock series is Balcombian or Janjukian. To meet this difficulty the wider term 
Barwonian has been given, as both these horizons are well developed in the 
Barwon Basin. 
Stratigraphical evidence also exists in confirmation of the above sequence in 
the Moorabool Valley, in the coastal sections from Port Campbell to Cats’ Reef 
and elsewhere. 
