106 Proceedings of the Royal Soeiety of Victoria. 



orthoclase felspar, and greenish mica. The upper portion 

 of the mass has a gneissose appearance, as if the mass had 

 been subject to hiteral strain and crushing, causing re- 

 arrangements of the constituents subsequent to its original 

 solidification from a plastic molten mass. 



To the south as at-Sardine Creek, on the Broadribb, the 

 middle portion of the Erinundra, on the Bemm, the heads of 

 Tongii Creek, and on the Cann at Morgan's, it has accessory 

 hornblende in places, is in fact syenitic. The age of these 

 granitic masses is probably Devonian : they form part of the 

 plutonic masses which invaded the Palaeozoic sediments at 

 the close of the Devonian period, and exposed b}^ subsequent 

 denudation. 



At the Yeerung River are masses of quartz, porphyry, and 

 felsites, also probably pai-t of the later Devonian volcanic 

 activities. So far as known at present, the Mesozoic series 

 are absent. 



Tertiary. — Miocene. 



The next defined group of rocks are the yello\y limestone 

 bands resting on the denuded surfaces of the Silurian or 

 granite rocks, and overlaid by bouldery wash clays, gravels, 

 and sand deposits. This formation is found near the coast, 

 well exposed cliffs are seen on the west side of the Snowy 

 near Orbost, and occasional remnants are met with on 

 the east side, yielding characteristic fossils. 



At Bonang, and in certain places along the western 

 watershed of the Broadribb River, are outliers of tertiary 

 basalt which appear to have filled the Miocene River valleys 

 although the surrounding hills have been degraded. At 

 Bonang, underlying the basalt there and on the western rim, 

 are outcrops of what at first would be considered a heavy 

 river bouldery deposit. Fm^ther close examinations suggested 

 to me that it was in reality a remnant of a Devonian 

 conglomerate (some of the watervvorn boulders are 3 feet in 

 diameter). The locality is about 450 feet above the Bonang 

 river. 



Unless these boulders are, as suofnrested, remnants of 

 Devonian heavy conglomerates (they are probably of glacial 

 origin), it is difficult to conceive of fluviatile agencies 

 transporting them along a comparativel}^ flat valley sach as 

 existed in situ durincj Miocene times. A little gold has been 

 obtained in some of the lighter gravelly wash associated with 

 the larger boulders. 



