Xll 
Parley Stage stable conditions supervened, perhaps accompanied l>v slight 
elevation marked by the development of the Greta Coal-Measures. These 
measures are about 130-200 feet thick, comprising at least two coal seams 
14-32 feet and 3-11 feet thick respectively, together with sandstones, shales, 
fireclays, and more or less coarse conglomerates. The most characteristic 
fossil plants are : — Gangamopteris, Glossopteris, Noegg erathiopsis, Annularia, 
and Vertebraria. 
At the close of the deposition of the strata of the Greta Coal-Measures 
marine conditions once more supervened, and the beds of the Upper Marine 
Series w r ere laid down. They are divided into a lower and upper stage, known 
respectively as the Branxton Beds, 3,000-3,400 feet thick, and the Crinoidal 
Shales, 1,500—3,000 feet thick. The basal bed of the Branxton Stage is 
formed of pebbly sandstone, passing upwards into mudstones, with occasional 
beds of sandstone, and the stage ends in very massive sandstones known as 
the Muree Beds, abounding in Strophalosia. The lowest of the Muree Beds 
has been named the Muree Bock, or Bolwarra Conglomerate, and is one of 
the most persistent horizons in the district. 
(c) The Wollong Horizon. — The upper foraminiferal horizon (Wollong 
horizon) is situated in the Branxton Beds, at a depth of between 100 and 200 
feet below the Muree Bock, and over 2,500 feet above the Greta Coal- 
Measures. The locality where Mr. J. E. Came, Assistant Government 
Geologist, and I, first observed the Eoraminifera is in Portion 112, in the 
Parish of Mulbring, County Northumberland. The spot was shown to us by 
Mr. Glennie Wyndham, of Wollong, and is situated on Mr. Dodds’ property. 
The Coral Trachypora W illdnsoni occurs there in great abundance, forming 
thin miniature reefs in the Upper Marine Mudstones. Numerous Eoraminifera 
are distributed through the mudstones in the vicinity of these corals, and 
samples of the weathered shales, from this spot, which were collected by 
Mr. G. Wyndham, and forwarded to Mr. E. Chapman, yielded, on washing, 
the best preserved foraminiferal shells as yet obtained from any part of the 
Permo-Carboniferous System of N. S. Wales. Bepresentatives of the 
Fenestellidce are numerous near this horizon, but the pencil-shaped variety of 
Stenopora, so plentiful at Pokolbin, was nowhere observed at Wollong, and 
Eurydesma cordata, a very characteristic form at Pokolbin, is wholly wanting 
at Wollong. Ice-borne erratics, from a few pounds up to over a ton in 
weight, are tolerably frequent in the strata, both above and below the Wollong 
foraminiferal horizon. 
