166 Proceedings of the Royal Society of Victoria. 



A rock represented by specimens in the conglomerates at the 

 Barwon Falls has been called gabbro. It gives us a better 

 indication as to the original character of one of the rocks of this 

 series. It (147) is an enstatite-diabase, not unlike some of the- 

 speciraens from Heathcote. 



A specimen from the Barwon Falls, Geelong (150), is normal 

 epidiorite, with the plagioclase well developed and the uralitic 

 hornblende abundant. 



An analysis of one rock from the outcrop near Geelong has 

 been given in Selwyn's " Descriptive Catalogue of the Rock 

 Specimens and Minerals in the National Museum," 1868, pp. 

 17, 94. It is identified as a "Greenstone (diabase)." The 

 analysis was interpreted to identify the plagioclase as labradorite, 

 and the green mineral as probably chlorite. The exact locality 

 of the rock is not stated.^ 



Greenstone (diabase), Geelong. 



Silica 50.84 



Alumina - - - - - - 12.92 



Sesquioxide of Iron - - - - 0.52 



Protoxide of Iron - - - - 6.99 



Lime ------- 14.35 



Magnesia - 10.97 



Potash 1.83 



Soda ------- traces. 



Water 0.71 



In south-western Victoria, near Mount Staveley, we have 

 another development of the Heathcotian rocks. They extend in a 

 band, coloured on Mr. Everett's Geological Survey Map of 

 Victoria- as " Porphyrites, Diorites, and Trachytoid rocks, &e." 

 This band extends north and south for some twelve miles. I 

 have been able to examine this bed near Mount Staveley, between 

 Wickliffe Road and Glen Thomson. This hill is mainly com- 

 posed of hard cherts of the Heathcotian type ; they are associated 

 with diabases, also like those of the Heathcotian series. The 

 ridge may be regarded as another exposure of the pre-ordovician 

 rocks. 



1 Ibid., p. 94. 



2 Geol. Survey, 1902. 



