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the species indicated by the impression received from Cairns 
Range. This fact I communicated to the Government Geologist 
of Queensland, which indicated the extension of the Ordovician 
rocks to the borders of that province, and the probability of their 
occurrence within its boundary. In acknowledging the informa- 
tion, Mr. Jack writes, June 7, 1895 :—‘ What renders the ques- 
tion of more than usual interest at present is that in some of the 
bores in the neighborhood of Boulia there are enormous thick- 
nesses of limestone which might possibly be either Ordovician or 
the older limestones, &c. (probably Cambrian), on which the 
Silurian lies unconformably. It is quite on the cards that there 
may be a barrier of Paleeozoic rocks extending from the Cairns 
Range to the Cloncurry.” 
Ata meeting of the Royal Society of Queensland, July 6, 1895, 
a& paper was communicated by the Government Geologist on 
“ Stratigraphical Notes on the Georgina Basin with Reference to 
the Question of Artesian Water,” from which and the discussion 
which ensued we learn that important advances in stratigraphical 
geology, as far as Queensland is concerned, are the outcome of 
the little episode attached to the fossil impression from Cairns 
Range. Mr. Jack argued that Paleeozoic and metamorphic rocks 
are continuous from the Cairns Range to the Cloncurry area, and 
consequently that the Lower Cretaceous area at the head of the 
Georgina River, as shown on the 1892 geological map, must be 
deleted. These Paleozoic rocks either outcrop or are very close 
to the surface. He bases these conclusions on the fact that un- 
successful bores have been put down at Carandotta, Chatsworth, 
Glenormiston, Marion Downs, and four on Tooleybuck Station ; 
also on the geological investigations in South Australia in the 
vicinity of the North-western border of Queensland. The only 
conclusion that can be drawn from this fact is that the country 
to the north of a line extending from the western boundary of 
the colony by the tropic of Capricorn to the Georgina River and 
thence north-eastward (perhaps not in a straight line) to the head 
of the Warburton River must be regarded as unfavorable for 
boring for artesian water. . | 
In the discussion which followed, Mr. Gibb Maitland drew 
attention to the fact that 25,000 square miles of country, believed 
to be artesian, is now shown to be made up of much older rocks. 
The discovery of rocks with Silurian or Cambrian fossils on the 
western border of Queensland is one of the most important strati- 
graphical facts recently ascertained in Queensland. The oldest 
fossiliferous beds were, until quite recently, believed to be Dev- 
onian, though the occurrence of sedimentary beds lying uncon- 
formably beneath these was not unknown. ‘The true age of the 
limestones of the Cairns Range and those met with in some of 
