Geological History in Palmzoic Times . 
67 
once overspread the whole of the intervening central portion of 
Victoria, but of which all but the two extremities have been since 
removed. In support of his views, Mr. Selwyn refers to the wes- 
terly inclination of the Grampian sandstone beds, with their abrupt 
east-facing precipices on the one side, and the west-facing preci- 
pices of Timber Top, Mount Wellington, and Ben Cruachan on 
the other, and he also cites the occurrence of isolated patches of 
Upper Palaeozoic rocks in the intervening country. At the time 
this was written, little was known of the geology of the eastern 
Upper Palaeozoic belt, and the aspect, at a distance, of such hills 
as Ben Cruachan and Mount Wellington favoured Mr. Sehvyn’s 
belief. The results of subsequent investigations, however, justify 
a considerable modification of the views expressed by Mr. Selwyn 
in 1866. The facts as regards the modes of occurrence of the 
Upper Palajozoic rocks are briefly as follows : — 1. The Grampian 
sandstones or western group flank and decline from the western 
slopes of the great central Lower Palaeozoic mass ; their original 
margin of contact with the latter has been cut through by denu- 
dation, and their eastern portion, wherever it may have once ex- 
tended to, has been removed ; their lithological character and the 
dip of their beds has favoured the development of the precipitous 
character of their eastern faces. 
2. The eastern group occupy a long and deep trough, hollowed 
back far into the central mass of Lower Paleozoic rocks, which 
form steep margins on all sides but that towards the coast. 
3. The outlier at Mount Tambo occurs similarly, though its 
containing hollow is at a greater elevation than that of the 
last-mentioned group, and has been cut off at either end by 
denudation. 
4. With respect to intervening patches, that at Wild Duck 
Creek is at a very low elevation above the sea, and I do not know 
of a single instance where a cappiug of Upper Palceozoic rocks 
has been met with on any of the higher mountainous country be- 
tween Mount Wellington, in Gippsland, and Mount William, in 
the Grainpiaus. The few conglomerate patches which do occur 
are at elevations considerably under 2,000 feet, and appear more 
nearly related to the Mesozoic rocks, which will be hereafter 
described, than to the Upper Palaeozoic. 
There can be no doubt whatever that during the Upper Palaeo- 
zoic epoch the country was submerged below the sea to a depth 
not less than 5,000 feet lower than it is now, and that previous 
to such submergence terrestrial and littoral denudation had eroded 
in the Granite, Silurian, Lower Devonian, and Middle Devonian 
rocks, the troughs and hollows which were afterwards filled by 
the LTpper Palteozoic beds. At the same time there is no reason 
to infer that the entire central rock mass was submerged. 
