64 DEVOIflAN KADIOLARIA FROM NEW SOUTH WALES. [Feb. 1 899, 



Discussion (on the two eoeegoing Papees). 



Mr. G. A. Stonier said that the paper was an important and 

 very welcome contribution to the geology of the north-eastern 

 portion of New South Wales, not only on account of the discovery 

 of radiolaria, but also because Lepidodendron australe was shown to 

 have had a greater range than had been previously supposed, and 

 the position of the garnetiferous limestone had been ascertained. 

 The tuffs were of particular interest to the speaker, as he had found 

 that near the diamond-properties at Bingara tuffs and volcanic 

 breccias were well developed ; they contain fragmentary shells, 

 and are interbedded with shales characterized by Lej)idodendron 

 australe. 



Prof. SoLLAS, in complimenting the Authors on their work, 

 commented on the shallow-water character of the deposits, and 

 maintained that radiolarian cherts were by no means an infallible 

 indication of abyssal conditions. The associated rocks in the 

 Arenig Series, Culm Measures, and, as we now know, in the Devo- 

 nian, were not of the nature of deep-sea deposits. 



Prof. Watts called attention to the great thickness of the radio- 

 larian deposit, and remarked that the extraordinary point about 

 this deposit and those in Devon, California, and Southern Scotland 

 was the entire absence of terrigenous material. The thickness of 

 the deposits indicated the lapse of a great interval of time. 



Dr. HiNDE, in reply, said that Prof. Sollas was under a mis- 

 apprehension in supposing that several conglomerates were inter- 

 calated in the series of radiolarian rocks at Tamworth ; the Authors 

 referred to one conglomerate which occurred in the highest part of 

 the section, and they doubted whether even this properly belonged 

 to the beds below it. The speaker still considered that the radio- 

 larian strata of New South Wales, also those of the South-west of 

 England and California, indicated deposition at a distance from land 

 and in deep water, though to Prof. Sollas this might seem an 

 ' irrational conclusion.' 



The President also spoke. 



