Upper Palaeozoic and Mesozolc Fossils. 319 



with true coiiii'erous wood. 'J'lie Cordaitean stem, for example, 

 exhibits in its secondary wood tracheides witli liordered pits, a 

 character for long supposed to be typical of Coniferous woods, 

 and, in fact, very closely respml)ling, if not identical with, that 

 of Araucaria itself. Undoubted stems of Cordaites have also 

 yielded in che earlier portion of the xylem the scalariform and 

 spiral elements commonly seen in many other plants. 



In the present instance the wood structure has been carefully 

 compared with sections of wood taken in various directions from 

 Araucaria cunninghami and Dammara australis. For the 

 opportunity of examining these recent woods I am indebted to 

 Mr. R. H. AValcott, of the National Museum. 



Occurrence of Palaeozoic Fossil Wood in Australia. — Silicified 

 stems and roots of trees have long been known to occur in the 

 upper palaeozoic strata of Queensland^ and New South Wales. - 



With regard to the Queensland occurrences Jack remarks on 

 the silicified wood exposed on the sides of Jack's Creek, as 

 follows'^: — "About a mile north of the Boweii River a thickness 

 of about fifty feet of greenish-gray .sandstone is seen, containing 

 numerous, large, drifted coniferous trees. The trees, which are 

 silicified to a black flint, and sometimes opalized, occasionally 

 I'etain some of the branching roots. Fragmentary plant remains, 

 in a carbonized condition, are also common. About half a mile 

 from the river the creek divides into two branches, both of which 

 show for some distance up sections of the greenish-gray pebbly 

 sandstone with silicified drifted trees. One tree measured thirty- 

 one feet in length and tapered from twelve inches to three inches 

 in diameter." 



The .same author mentions other large silicified trees, about a 

 quarter of a mile west of Rosella Creek, in one of which he 

 counted about thirty rings of growth. 



Of the Upper Bowen formation of Walker's Creek, Jack 

 remarks'* : — " Some sandstone beds in the neighbourhood contain 

 silicified logs, and similar logs, evidently weathered out of the 



1 Etheridge, Jun., and Jack. Geol. and Pal., Queensland, 1892, pp. 165, 166, 168, 17."). 



2 Nicol, Edinbur<rh New Phil. Journ., vol. iv., 1832, p. 153; Clarke, Quart. Journ. Geol. 

 Soc, vol. iv., 1848, p. 60; Dana, Geol. U..S. Expl. Exped., 1849, p. 714; Eth. ,hin., Cat. 

 Aust. Foss., 1878, p. 32 (footnote c). 



3 Tom. cit., p. 165. 



4 Tom. cit., p. 168. 



