20 STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 



In New South Wales,-" strata seen on the Clarence River Dis- 

 trict have some insignificant streaks of coal and the flora has Juras- 

 sic affinities. The rocks are conglomerates, sandstones and shales, 

 and the coal seams are unimportant. The Wianamatta beds, about 

 700 feet thick, are older and more argillaceous. Entomostraca 

 occur in the upper layers. The coal seams are, at most, only a few 

 inches thick. The Hawkesbury series, resting on the Permo- 

 Carboniferous, is about 1,000 feet thick and consists of yellowish- 

 white sandstone with a few beds of shale and conglomerate and 

 some streaks of coal, without economical importance. The sand- 

 stones show much false bedding, usually directed toward the north- 

 east, but reversal of the currents is evidenced by occasional inclina- 

 tion in the opposite direction. Contemporaneous erosion of the 

 sandstones is proved by old channel-ways filled with gravel and 

 angular bowlders are not rare. Wilkinson thought the false bed- 

 ding due to currents in shallow water; but he cites J. E. Tennison- 

 Woods, who asserts that the peculiar structure is evidence that these 

 sandstones are a wind-blown formation. Plant leaves and frag- 

 mentary stems as well as remains of fishes are in both formations 

 but no remains of marine animals had been discovered. The later 

 studies of the New South Wales geologists make it clear that the 

 relations of the Wianamatta and Hawkesbury to the Triassic are 

 very close. 



Triassic. 



The term Trias is of German origin ; on much of the continent, 

 the system is triple or was recognized as triple, being divided into 

 the Keuper, Muschelkalk and Bunter. In later years, the Rhsetic or 

 Infra-lias has been taken to be more closely allied to the Trias, so 

 that now the divisions are four. 



Within Great Britain, Rhsetic, Keuper and Bunter have been 

 recognized, but the IMuschelkalk or limestone division seems to be 

 wanting. The several formations consist of conglomerates, shales, 

 marls and sandstones ; the Bunter in considerable areas passes down- 

 ward gradually into the Permian. Rock salt and gypsum are in the 



2^ C. S. Wilkinson, " Notes on the Geology of New South Wales," DepL 

 of Mines, Sydney, 1882, pp. 53-55. 



