162 Proceedings of tJie Royal ISocieti/ of Victoria. 



conglomerate of grey colour ; grey, greeuisli-brown, yellow, bluish- 

 grey, white, grey and black plain cherts, and black, grey, white, 

 brown and dark-blue mottled cherts ; a grey-coloured rock like 

 quartz felsite ; white and pale yellow chalcedony, with very 

 pitted ragged edges; carnelian ; chalcedonic breccia; brown 

 spherulitic rock like quartz-felspar-felsite ; silicitied wood ; and 

 an igneous I'ock that looks like a very dense basalt or 

 melaphyre. It is a crystalline rock with felspar and small green 

 crystals like olivine, and is of medium grey colour. 



Some of the cherts have a fragmental appearance, and they all 

 are extremely like the rock of some of the pebbles of the 

 Cainozoic gravels of the Povvlett and Tarwin Plains. They have 

 undoubtedly been derived from the same source, or from similar 

 rock masses. 



The silicified wood has the same general appearance as much 

 of that found among Jurassic strata in the State. A micro- 

 scopical examination is, however, necessary before a conclusion 

 can be arrived at as to its Jurassic age. Certainly the Silurian 

 or older strata did not furnish it, and there is no evidence of the 

 occurrence of any younger Palaeozoic strata anywhere near this 

 district, even if plants of the nature represented by the wood 

 flourished during those periods. The silicified wood may, never- 

 theless, belong to the Carboniferous or Devonian period, and 

 have been transported in a silicified state by driftwood, floating 

 ice or floating islets far from its home. The occurrence of 

 large blocks and small trees lying prone among fine and coarse 

 sandstones, and including among the roots of the trees a bluish 

 or olive mudstone quite distinct from the containing strata, 

 clearly indicates their driftal origin. 



Should, however, this silicitied wood be determined as Jurassic, 

 it proves that silicification of some at least of the carbonaceous 

 material in the Jurassic strata was carried out during the 

 Jurassic period. 



Volcanic Neck, 3. 



This neck lies to the north-east of Neck 2, and about 6 chains 

 distant from its northern end. Jurassic strata occupy the inter- 

 vening area, as evidenced by the soil, and pieces of rock in water 

 channels. 



