president's address. 577 



Dawson."^' If this fossil plant be referable to the Coniferte, it 

 forms the first conclusive evidence of the existence of a contem- 

 poraneous land flora in Australasia, and confirms the proofs of 

 the existence of a contemporaneous land surface afforded by the 

 suncracks in the sandstones. 



Messrs. Jack and Etheridge considerf the Burdekin Formation 

 (Middle Devonian of Queensland) to be homotaxial with the 

 Buchan and Bindi Limestones of Victoria. 



C. Devonian, Lower, Middle or Upper. — (1) In New Zealand 

 from Silurian time up to the commencement of the Permo-Carbo- 

 niferous (?) Period sediments were continually deposited, without 

 marked unconformability, until the system termed by Professor 

 Hutton the Takaka System had attained the almost unprecedented 

 thickness of about 100,000 feet in Otago.| This immense system 

 of rocks, having a thickness of nineteen miles and now uplifted 

 and so denuded that what were the lowest beds are now exposed 

 to view, should afford very important evidence as to the thickness 

 and constitution of the earth's crust. 



It might naturally have been expected that such a vast amount 

 of sedimentation by its downward bulging of the earth's crust 

 would lead sooner or later to exceptional volcanic outbursts. 

 The Dun Mountain eruptive series, which Sir James Hector 

 considers contemporaneous with the upper part of the Takaka 

 (Upper Devonian), or with the base of the Maitai Series (Carbo- 

 niferous), consists of the unique ultrabasic rock, dunite, and an 

 enormous thickness of " greenstone breccias, aphanite slates, 

 diorite sandstones, tfec." 



(2) In West Australia Mr. E. T. Hardman has described § rocks 

 of Devonian C?) Age at the Rough Range in the Kimberley Dis- 

 trict as containing Stromatopora, corals, Spirorbis, SerpnlcE, &c., 

 some of Devonian, others of Carboniferous affinities. In his later 



* Q.J.G.S. 1881, xxxvii. p. 306, t. 13, fig. 15. 

 t Loc. cit. p. 45. 

 X Q.J.G.S. May, 1885, p. 199. 

 § Report on the Geology of the Kimberley District, West Australia, p. 17. 



