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is, I believe, to be found in tbe sun-drying and peeling-ofE of flakes of the shale and 
their subsequent partial rounding by attrition. I say this by way of caution agains 
hasty conclusions from future discoveries. In the very probable event, for instance, 
of the discovery in shale- shingles of a determinable fossil— say, Lepidoiendron australe 
—the conclusion would be that the conglomerate containing tbe shingle was deposited 
in a geological age subsequent to the deposition of the shale containing Lepidodendron 
australe, and, in my belief, the conclusion would be erroneous. 
At the intersection of the road from Thornborough to Glen Mowbray with that 
which leads up to the Pioneer and Tichborne Mines is the outcrop of a bed of con- 
glomerate, in which pebbles, up to six or eight inches in cHameter, are closely packed 
in a matrix of greywacke. Of these pebbles some are of greywacke, the majority 
quartz, and a fair pi'oportion blue coralline limestone. Similar limestone pebb 
found in conglomerates in a number of other places— e.y., on the hill west of the City 
of Dublin Eoef, on the roadside in Gleu Mowbray, near the junction of the Thorn- 
borough and Kingsborough roads, in the gully west of the shambles in Glen Mowbray, 
and in Tyrcoimell Crock, north of the Honest Lawyer. 
As ill the case of tbe shale-shingles of the Glen Mowbray Conglomerate, I con- 
sidered it very doubtful whether the fossils in the limestone _ pebbles were really 
“derived” from an older formation, having observed that the shingles on the Pacihc 
coast of the present day contain numerous pebbles and boulders of coral drifted rom 
the Barrier or other reefs. In this view I was subsequently confirmed by the discovery, 
about a mile and a-half south-west of Beaconsfleld, of a conglomerate with similar 
pebbles containing similar fossils, almost immediately adjoining a bed of limestone whicd 
has been quarried for mortar for the Antimony Smelting Works at Northcote. is 
bed of limestone is vortical, four feet at least in thickness, and strikes north-north- wes , 
as do all the strata in the neighbourhood. The limestone was found to contain a num er 
of corals and shells, amomr which my Colleague has recognised Paeliypora, sp. tnd ana 
Cyatliopliylhm, sp. ind. (P“l. 3, f. 10). Without attempting to name any more of the 
corals, which are in indifferent preservation, it is easily seen that several species are 
common to the limestone bed and to the limestone pebbles in the conglomerate, ibe 
corals which weather out in relief from the limestone pebbles of the conglomerate may 
therefore be ranked as contemporaneous with the strata of the goldfield. ^ 
The discovery of Lepidodendron in the Gympie Beds at the Training Wa 
Quarries, Itoekhampton, removes one formidable objection to classing the Hodgkinson 
Beds with the Gympie Beds. As long as Lepidodendron was believed to be confined o 
the Star Beds, its occurrence in the Hodgkinson strata seemed favourable to placing t e 
latter on a horizon near the former. We have here a second instance of the occurrence 
of Lepidodendron associated with a marine fauna iu one and the same bed.’^ 
The auriferous reefs of the Hodgkinson are well defined, and are divisible into 
two groups or orders. Those of the first group coincide in their strike with the strike 
of the strata in which they occur. To this group belong the Tasmanian, North Star, 
Outward Bound, Amy Moore, Vulcan, Britannia, Caledonia, Forget-me-Not, Von 
Moltke, Lady Mary, Mark Twain, Bob Boy, Garry Owen, Tyrconnell, Black Prince, 
Henry Grattan, Commodore, Lizzie Bedmond, Hero, Pioneer, Hope, and others. In a 
the members of this group a general law may be observed. They underlie at right ang e 
to the dip of the strata. This circumstance can only mean that the fissures were producen 
by the same pressure that upturned the strata. Each stratum would break along » 
plane of least resistance, which would be found at right angles to the planes of beddi^ 
* See Annual lleport of tho Department of Mines, N.S.W., for 1889, p. 239. 
