1 74 Proceedings of tJie Royal Society of Victoria. 



heds ; (2) the Warrandyte anticlinal ; (3) the Lillydale synclinal ; 

 (4) the anticlinal of the Upper Yarra, in the centre of which, near 

 Matlock, upper ordovician rocks are exposed ; (5) the geosyn- 

 clinal of Walhalla. 



7. The heathcotian I'ocks are the fragments of the old frame- 

 work upon which Victoria has been built. 



EXPLANATION OF PLATES XXIIL-XXVI. 

 Plate XXITI. 



Sketch map of the distribution of land and sea in Victoria in ordo- 

 vician times. The areas in black are the present 

 outcrops of the Heathcotian series. In upper ordo- 

 vician times there was a transgression of the sea 

 round the northern end of the Colbinabbin Range and 

 into the Upper Yarra. 



Plate XXIV. 



Fig. I. — Map of part of Heathcote, showing diabase series in 

 part between the metamorphic rocks of the ordo- 

 vician, and also the overlap of the ordovician across 

 the metamorphic series. From the Geological Survey 

 Map of Mr. O. A. L. Whitelaw, as reduced in 

 Howitt's Memoir. 



Fig. 2. — Map of the relations of the ordovician and meta- 

 morphic rocks, near South Heathcote. After O. A. 

 L. Whitelaw. 



Fig. 3. — Copy of Mr. Lidgey's map of part of Crosbie, represent- 

 ing the overlap of the ordovician rocks across the 

 metamorphics. 



Fig. 4. — Copy of Mr. Lidgey's map of part of the parish of 

 Knowsley. 



Plate XXV. 



Fig. 5. — Diagrammatic section showing the relations of the 

 ordovician, lieathcotian, and silurian rocks, near 

 Lancefield. 



