118 Proceedings of the Royal Society of Victoria. 



bedrock. They appear to be at the base of or older than the 

 Mesozoic strata. 



I presume that the conglomerates Mr. Murray mentions were 

 locally formed from the wreck of the Silurian rocks upon which 

 they rest. 



The geologists I have quoted all agree that some of our reef 

 fissures in Silurian rocks were filled with auriferous quartz at 

 the time when the Silurian strata were upheaved, folded and 

 crushed, and more or less metamorphosed, and they place that 

 time somewhere between the end of the Silurian period and 

 the final part of the Upper Palaeozoic period when a great break 

 in the stratigraphical succession occurs in our Victorian Geology. 

 From my own observations in the field I can agree with the 

 authors whose views I have reviewed, but I go further, and con- 

 sider it possible that we may have in Victoria an auriferous Upper 

 Silurian conglomerate. To illustrate this opinion I may perhaps 

 be permitted to refer to the geology of the lower part of Wombat 

 Creek, a tributary of the Upper Mitta Mitta River, where there 

 is an unconformable junction between the Lower and the Upper 

 Silurian rocks. The lower series consist of slates and sandstones 

 and quartzites in parts metamorphosed ; these rocks are probably 

 of the same age as the schists of the Glen Wills goldfield. Near 

 the Upper Silurian rocks the slates of the older formation are 

 folded sharply into anti- and synclinal folds. From one anticlinal 

 fold, within a chain or two of the conglomerate, I took grap- 

 tolites, decided by Mr. T. S. Hall, M.A., to be of Lower Silurian 

 age of the Victorian Geological Survey, or as he prefers to call 

 it, Ordovician.^ 



The basal bed of the Upper Silurian rocks is a bouldery con- 

 glomerate, some of the stones measuring three feet in diameter. 

 Tins is succeeded by finer conglomerates, sandstones, shales and 

 limestones ; the shales and limestones are in places crowded with 

 corals, shells, and trilobites, determined by Mr. R. Etheridge, 

 jr., to be of Upper Silurian age.'-^ Lithologically and strati- 

 graphically the upper and lower series of rocks present a striking 

 unconformability to each other. Tlie upper rocks ai-e not 



1 Proc. Roy. Soc. Victoria, N.S., vol. ix. 



2 Progress Report, No. 10, Geo. Survey, Victoria, jip. 100 and 101. 



