BY A. B. WALKOM. 143 



of the N.N.W. mountain range just mentioned, accounts for the 

 absence of the Greta Coal-Measures between Wingen and 

 Ashford. 



In the Drake district, some of the marine deposits have a 

 fauna which consists of a mixture of Lower Marine and Upper 

 Marine types, and it seems almost certain that, during the time 

 of deposition of the Greta Coal-Measures in the inland basins, 

 marine sedimentation was going on in this area. This means 

 that there was continuous marine sedimentation from Lower 

 Marine into Upper Marine time in the Drake area. 



After the deposition of the Greta Coal-Measures, the sea broke 

 through the eastern land-barrier in its southern part, and sub- 

 merged an area extending some distance north of Gunnedah, 

 bounded on the west by the older rocks (Devonian, Silurian, and 

 Ordovician) that we see at Marulan, Mt. Lambie, Bathurst, Wel- 

 lington, etc. The northern shore of this arm of the sea was 

 probably somewhere in the neighbourhood of the Peel Range and 

 the Manning River, and the land for some distance north of the 

 Manning seems to have extended further to the east than the 

 present coastline. The Drake district was also submerged at 

 this time, and the coastline appears to have been something like 

 that suggested on the map( Plate xii.). 



At the close of Upper Marine time, the pushing force once 

 more made itself felt, and the result was that once again a land- 

 barrier was raised, and another series of inland depressions 

 formed. In New South Wales, the great inland basin in which 

 the Upper Coal-Measures were laid down, was approximately as 

 shown in Plate xiii., and it is probable that here, for the first 

 time, there was direct water-communication from the Hunter 

 River Basin to Queensland west of New England. 



The land, at this time, to the east of the central part of the 

 present coastline, was not far away, and must have been of some 

 considerable height, as proved by the coarse conglomerates with 

 diagonal bedding, dipping strongly inland, which Professor David 

 has described at New Lambton and Red Head.* 



* Mem. Geol. Surv. N. S. Wales, Geology, No.4, pp.20 aud 41. 



