562 RADIOLARIA IN PALAEOZOIC ROCKS, 



G. J. Hinde had placed at my disposal, on leaving England, a 

 valuable collection of British Palaeozoic radiolarian rocks, which 

 jjroved of the utmost use for purposes of comparison. A large 

 number of sections of the red jasper proved conclusively that 

 radiolarian rocks were developed on a large scale both at Barraba 

 and Bingera. It is the opinion of Mr. E. F. Pittman, the Govern- 

 ment Geologist, that the red colour of the jaspers was the original 

 colour of the beds at the time of their deposition and that it is not 

 due simply to contact metamorphism. A collection of specimens 

 kindlj' made for me by Mr. Pittman confirms this theory. The 

 question as to whether these red jaspers are altered "red clays" 

 of deep sea origin will be discussed later. The geological horizon 

 of the red jasper may be provisionally placed somewhere in the 

 Devonian System, perhaps in the Middle Devonian, homotaxial 

 with the Burdekin formation of Queensland. 



Lepidodendron Australe occurs in some quantity in rocks 

 which seem to be somewhat newer than the radiolarian beds; 

 but it appears to be represented sparingly, almost, if not quite, as 

 low down as the horizon of the radiolarian rock. This, however, 

 is not yet an established fact. 



(3) Tamworth. — Traced southwards, the radiolarian beds have 

 recently been found by me to attain a remarkable development 

 in the neighbourhood of Tamworth. They there consist of 

 siliceous, dark bluish-grey, calcareous rocks, fine-grained blackish- 

 grey claystones and cherts, and coralline siliceous limestone. 

 The coralline limestone beds, of which there appear to be at least 

 two, are from 100 to 1000 ft. in thickness, and are composed 

 chiefly of the following fossils : — Strotnatopora, Cy.athophyUum, 

 DiphypJii/U um Porteri, Cystiphylluin, Favosites gothJandica, and 

 F. grandipora or Pachypora (the latter very abundant and 

 characteristic). Alveolites (also very abundant), and Ileliolites. 



Mr. Donald A. Porter, of Tamworth, conducted me to the spots 

 where these limestones can be studied to best advantage, and 

 he concurs with me in my provisional deductions with regard to 

 the Tamworth rocks. 



