204 



is not invariable. According to Messrs. Hall and Pritchard, the 

 reverse is the sequence in the Geelong district. As a fact, the 

 fossil evidence indicates a close relationship between the two sets 

 of strata, and we class them both as Eocene. 



The recognition, a few years ago, both in Victoria and South 

 Australia, of deposits of undoubted Miocene age, but of quite 

 different lithological character to the prevailing calciferous rocks 

 mentioned, supplied fresh data for the classification of the ter- 

 tiaries. They invariably overlie both the so-called Oligocene 

 and the calciferous rocks, and are usually demarked off by an 

 eroded surface, while the general facies of their molluscan fauna, 

 as well as the percentage of living species represented, definitely 

 fixes their geological horizon. They are succeeded in South 

 Australia by fossiliferous strata provisionally referred to the 

 Older Pliocene. In Victoria the latter are w^anting, but a 

 younger member of the same group is known, and the tertiary 

 series is thus fairly complete. If, then, the middle member of 

 the series be Miocene, how can the inferior one, with its very 

 much smaller percentage of recent species, be placed on the same 

 horizon 1 



Compared with the Eocene, the marine Miocene and Pliocene 

 are of limited development, the great mass of our tertiaries 

 belonging to the oldest of the three periods. In fact, it requires 

 careful search to recognise them at all, and they were evidently 

 overlooked l)y the pioneer geologists. This is the only feasible 

 explanation of the serious blunder committed in referring nearly 

 all our wide-spread tertiary deposits to the Miocene period. 



In support of the opinions here expressed, it will be necessary 

 to refer briefly to the chief outcrops of the marine tertiaries in 

 Victoria and South Australia, beginning with the Eocene. 

 Details will be given only when the beds have not previously 

 been describe:!; for the rest the original papers maybe consulted. 



EOCENE. 



The rocks of this period commence at the Snowy River, in the 

 €ast of Victoria, and extend with numerous breaks along the 

 south coast to beyond the westerly boundary of South Australia; 

 they are also visible inland at various localities in both colonies, 

 and appear as outliers of limited mass on the north-west coast of 

 Tasmania."^ 



The sections in Victoria already described are : — 



Mitchell River, Bairnsdale;! Moorabool and Barwon Rivers;! 



* Vide Trans. Roy. 8oc. N.S.W., vol. XXII. , 1888. 



'^ Reports of Progress, Xos. 2 and 4 Geol. Snrvey of Victoria; Roy. 

 8oc. of Vic, vol. III., 1891. 

 t Ibid, vol. IV., 1892. 



