284 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 24, 



The Burrum coal-seams, worked for some time on a branch of 

 the Mary river, lie below the Maryborough C7/pr2nffl-sandstones ; 

 and their relation to the Wollumbilla- and Gordon-Downs series has 

 yet to be unravelled. 



The idea which seems to offer the greatest amount of feasibility 

 is, that contemporaneous with the deposit of a succession of marine 

 beds to the westward of the dividing range, at a period in time ex- 

 tending through the Oolitic and part of the Cretaceous period, a vast 

 lacustrine deposit was accumulated over a large area to the east- 

 ward of the same range, to which the sea obtained access after a 

 very considerable thickness of freshwater beds had been piled up. 



Beds of coal are a marked feature in these Mesozoic lacustrine 

 beds, whilst their supposed marine equivalents to the westward are, 

 as far as we have any observations on the subject, entirely devoid 

 of that valuable mineral. 



The appearance of these lacustrine coal-measures differs in a very 

 marked manner from their supposed marine representatives to the 

 westward. Coarse grits and thick-bedded sandstones form the ma- 

 jority of the strata, though shales, mudstones, and limestones are 

 interstratified throiighout the system. 



The physical difference is even more marked ; level plains desti- 

 tute of timber characterize the one, whilst broken ridges, covered 

 in great measure with dense scrub and fine timber, are the atten- 

 dant features of the other. 



It is of great importance to the future of the colony to ascertain 

 if the carbonaceous division of the Mesozoic formation is represented 

 in any portion of the western plains between WollumbiUa and the 

 Upper Flinders. If so, the coal-fields of Queensland would, indeed, 

 be inexhaustible, and a stimulus might thus be given to the con- 

 struction of that natural trunk-line of railway for Eastern Australia 

 (first suggested by the Hon. J. Grant, late Minister of Lands in 

 Victoria), from the Murray to the Gulf of Carpentaria. The neces- 

 sity for this will become the more apparent when the rich gold- 

 fields and mineral lodes of Northern Queensland are somewhat more 

 developed, and when these western plains, the richest pasture in 

 Australia, are fully stocked with cattle. 



It is hoped that the determination of groups of fossils from the 

 localities here mentioned may form bench-marks, so to speak, for 

 future observers who may work this practically interesting subject 

 to a more definite conclusion ; and the leading minds and students 

 of physical science in the colony look with anxiety to the parent 

 societies of England to aid them in their attempts to decipher the 

 structure and past history of this great area, whose yet unrecorded 

 facts must yield only to patient labour. 



Mineral Springs. — There is one other subject of practical interest 

 connected with the great western Mesozoic plains ; and that is the 

 occurrence of hot alkaline springs, which suggest the possibility of 

 obtaining supplies of water on the Artesian principle over some por- 

 tion at least of this area. 



At Gibson's Cattle-station on the Saxby river, a tributary of the 



