CARBONIFEROUS AND PERxMO-CARBONIFEROUS ROCKS, N.S.W. 335 



Wales the Wallarobba and Rocky Creek conglomerates, in 

 Queensland the conglomerate of the Star series, in U.S.A. 

 the Maroon Conglomerates of Colarado and the Potts ville 

 Conglomerate of the Eastern States, and in Europe the 

 Millstone Grit Series bear impressive testimony as to the 

 magnitude of the mountain-building movements, and the 

 denudation by which they were accompanied. The fluvio- 

 glacial conglomerates and tillites associated with Rhacop- 

 teris, recently discovered by Mr. C. A. Sussmilch, at Seaham, 

 and similar beds just discovered 200 miles northerly by Mr. 

 W. R. Browne at Currabubula near Tamworth, prove that 

 in Australia the glaciation which ended probably in Lower 

 Permian time commenced as far back as Middle Carboni- 

 ferous time, and probably attained its maximum in Upper 

 Carboniferous time. 



The evidence of the large erratics in the Caney Shales 

 of Oklahoma, the great blocks in the Maroon Conglomerates 

 of Colorado, the thick masses of breccia formed of erratics 

 occasionally striated in the St. Etienne coal-field of Central 

 France, and the groups of large cobbles in the fine shales 

 of the Upper Culm at the Frankenwald in Germany all 

 point to a world-wide development of glaciers in or about 

 Middle Carboniferous time. These great orogenic move- 

 ments in Eastern Australia continued throughout Uralian 

 (Upper Carboniferous) time into the Permian, but entirely 

 ceased before Upper Permian time. The maximum glaci- 

 ation appears to date to an epoch in Upper Carboniferous 

 time. The duration of the glacial conditions at all events 

 in Australia, must have been very considerable for reasons 

 already given. It is not unreasonable to suppose that the 

 interval in time represented by this great thickness of 

 strata may extend from low down in the Upper Carbonifer- 

 ous into the Lower Permian. 



13. (a) The great tectonic movements of Middle and 

 Upper Carboniferous and Lower Permian time, if not the 



