76 ON THE WAIANAMATTA SHALES 
hollows previously existing, or contributed patches forming con- 
siderable masses as well as thin layers to the uppermost Hawkes- 
t is difficult to gather the meaning of the author in this 
passage. He speaks of a “basin which fills in the area between 
a surrounding enclosure of the former series.” One would imagine 
tha ormer series” here referred to is the Hawkesbury 
formation, but he goes on to refer to the series as being “ broken 
up and denuded either completely before or during the deposit of 
the sandstone,” Clearly here the rocks referred to are paleozoic 
in. The difficulties of all these positions will be dealt with in 
the following paper. 
Mr. Clarke then goes on to speak of the fossil fish found in 
these shales, also of varities of iron ore, fossil wood, plant im- 
of which Bulbunmatta or Razorback Range and Menangle Sugat- 
loaf are outly ing relics of a once wider extended plateau.” 
Mr. Beete Jukes also refers to Mr. Clarke’s conclusions, and 
coincides with them. In a paper read before the Geological 
Society of London in 1847 see vol. iii-iv, p. 224), he describes 
these shales as 300 feet thick, lying on the top of the Hawkesbury 
sandstone 
and other hills in the neighbourhood of Campbelltown, are the 
outliers and fragments of what was once a plateau of Wianamatta 
