1114 ON THE BILOELA LABYRINTHODONT, 



which underlie the strata containing the abovernentioned marine 

 carboniferous fauna, and which, therefore, may claim paleozoic 

 age, we have Glossopteris Browniana, which reappears in the 

 Newcastle beds, but no higher ; and G. primceva, G. Clarkei, and 

 G. elegans, which do not survive, but are replaced by G. linearis, 

 G. ampla, G. reticulum, G. cor data, G. tteniopteroides, G. Wil- 

 kinsonii, and G. parallela. The lower beds also contain Noeggera- 

 thiojysis prism, and Annularia australis ; the upper N. spatliulata 

 and N. media. Of these Annularia, Phyllotheca, and Vertebraria, 

 appear also in the Newcastle upper coal (or Permian) beds, with 

 many other species, including Conifers. A ganoid fish, \Urosthenes, 

 is associated with them in the same beds. The natural conclusion 

 then will be that this Upper Coal is really of Permian age, at 

 least in the homotaxial sense. 



This conclusion is corroborated by an examination of the overlying 

 Hawkesbury beds, whose Triassic character has been frequently 

 pointed out by the Indian geologists, and seems to have been finally 

 acquiesced in by the late Rev. W. B. Clarke, who had previously 

 regarded them with the Wianamatta above, and the Newcastle 

 Beds below, as really Upper Carboniferous. (Southern Gold Fields, 

 p. 246 sqq.). With reference to this point we observe — First, that 

 the Newcastle Beds, belonging to the (Permian 1 or) Upper Coal 

 measures, had undergone considerable denudation before the 

 commencement of the deposition of the Hawkesbury Sandstone, 

 as Mr. Wilkinson has shown from a section upon the falls of the 

 Shoalhaven, and as I have myself observed at Lake Macquarie, so 

 that an interval of some length is here indicated, though its duration 

 cannot at present be more than guessed at. Yet after a careful 

 consideration of the very scanty information which is supplied us 

 by the rare and imperfectly preserved fossils of the Hawkesbury 

 formation, most geologists will probably agree with Mr. Wilkinson in 

 arranging it, homotaxially at least, with the Triassic of other regions. 

 For the characteristic plants of the Newcastle Coal Measures 

 have disappeared. We find no more Glossopteris nor Vertebraria. 

 But we find in their place a large and robust fern, if fern it be, 

 Thinnfeldia odontopteroides, which is common to both Hawkesbury 



