18 QUEENSLAND FOSSIL FLORAS 
the Burrum Series at the base of the Cretaceous, then the 
Rolling Downs Series would be Upper Jurassic. A critical 
revision of the fauna of the latter would help in the solution 
of this problem. 
This affords an excellent example of the advance in 
the study of fossil plants during recent years, and shows 
that they must now be ranked as of considerable importance 
in determining geological horizons. 
(iit) The flora of the Styx Series. From the Styx 
Series a collection of fossil plants has been obtained by 
the Geological Survey, and the results of the examination 
of this material are being published with the description 
of the Burrum flora. The flora of the Styx Series 
comprises, as at present known, fourteen species, as 
follows :— 
Equisetites sp. Teniopteris howardensis 
Cladophlebis australis Araucarites sp. 
Nathorstia (?) Willeoxi, sp. nov. 2Sphenolepidium sp. 
Phyllopteris lanceolata _ Podozamites sp. 
Microphyllopteris gleichenioides ?Celastrophyllum cf. Hunteri 
Otozamites cf. queenslandi ?Celastrophyllum sp. 
Temniopteris spatulata Phyllites sp. 
The combination here of certain species characteristic 
of typical Mesozoic floras with a few undoubted Angiosperms 
stamps this flora at once as of Cretaceous age. In the field 
the Styx Series occupies a small isolated area, and field 
evidence gives little indication of its age. The determina- 
tion of the contained fossils is, therefore, important in 
fixing the age of the Series. 
There is a considerable degree of resemblance between 
the Styx flora and the Patapsco flora of North America, 
which has been referred to the Albian Stage of the 
Cretaceous by Professor E. W. Berry. Nearer home, 
there is a scanty Cretaceous flora’ occurring at Waikato 
Heads in New Zealand which Arber has referred to the 
Neocomian Stage on rather meagre evidence. The Styx 
flora also shows considerable resemblance to this Waikato 
Heads flora. 
The predominance of typical Mesozoic (Triassic and 
Jurassic) forms in this flora indicates a Lower Cretaceous 
