164 Proceedings of tJie Royal Society of Victoria. 



the igneous aud the metamorphic rocks were of pre-ordovician 

 instead of post-silurian age. 



VI. — The Distributiox of the Heathcote Series in 

 Victoria. 



"We must enquire where else in Victoria representatives of the 

 Heathcote series occur. South of the Colbinabbin Range of the 

 Heathcote Valley we find a similar rock series forming the Mount 

 William Range, and extending from Mount William to south of 

 the Lancetield Gap. The distribution of the rocks is well shown 

 in the quarter sheet of the Geological Survey Map (Xo. o, S.E.), 

 where they are marked as '"Trap or Hypogene and metamorphic 

 Silurian." The famous aboriginal quarries of Mount William were 

 worked in outcrops of the amphibolites and impure nephrites of 

 the Heathcotian series. 



Mr. W. H. Ferguson^ has shown that at Dookie there is 

 another outcrop of diabases, and some specimens that he collected 

 {now in the Mines Deparment) show that both the igneous and 

 the associated metamorphic rocks have the characters typical of 

 the Heathcotian series. 



The bores put down by the Mines Department at Rushworth 

 have revealed beneath the silurian sandstones and shales a thick 

 series of hard black quartzites. I have had sections prepared 

 from these rocks and they show that these deeper Rushworth 

 quartzites have the characters of the Heathcotian cherts. Mr. 

 A. M. Howitt has re-examined the bore records of the Rush- 

 worth bores and has sorted out the sample of the cores. The 

 non-success of the boring for gold at that locality was due to the 

 fact that the deeper bores passed into the barren series of 

 Heathcotian cherts. 



That the Heathcotian rocks had at one time a considerable 

 extension further east than Dookie is probable from the evidence 

 of the glacial conglomerates between Chiltern and the Springs. I 

 have been guided over these deposits by Messrs. S. Hunter and 

 A. W. Gahan. The most abundant foreign boulders in these 

 deposits are cherts of the Heathcotian series. They are 



1 W. H. Ferguson : Notes on the Rocks at Dookie. Prog. Rep. Geol. Surv. Vict, No. 

 viii^ pp. 59-60, 1894. 



