Additional Notes for Students. 345 
the vast thickness of sediments that are embraced 
within the limits of the Permo-Carboniferous and 
the higher beds of the Hawkesbury-Wianamatta. 
Also, as to the nature of the country denuded. 
7. Are the Wianamatta Shales a distinct “ formation? ” 
8. Are Shales, corresponding to the uppermost beds of 
the Wianamatta Shales, in lithological as well as 
in palaeontological characters, found occurring at 
various horizons in the Hawkesbury-Wianamatta 
Series > 
9. Has the coastal region around Sydney been under 
water at any period since Jurassic times ? 
10. Professor David points out that the fault which 
was supposed to exist at Lapstone Hill is a 
monoclinal fold. Information will be acceptable 
as to the extension north or south of this fold or 
fault, as the case may be. 
11. A more fascinating, if more difficult, subject for 
research is opened up by the discussion of, from a 
geological standpoint, the introduction of existing 
plants and animals to Australia. In fine, any 
evidence as to man having a geological history in 
Australia would arrest the attention of the most 
eminent scientists of the age. 
12. The shales about Sydney are often faulted and 
broken. No very definite information is available 
as to the extent or the causes of this faulting. 
Fig. 81 shows some beds of Narrabeen Shale lifted 
and broken into an anticline, while the under- 
lying strata are undisturbed. The lifting is due 
