PART 4.] 
Feistmcmiel: Correlation of the Gonihodna Flora, 
251 
to tlie Bacelius-marsh sandstones a position whicli •would bring them on about 
the horizon of the Ha-wkosbury beds in Now South Wales. This seemed natural, as 
the Bacchus-marsh sandstones are considered as Lower Mesozoic, > and the Hawkes- 
bury beds ovei’lying the upper coal-measures or New-castle beds were treated of 
by the late Rev. W. B, Clarke under the heading “ Mesozoic or secondary 
formations. 
I have since received sevei-al communications from Mr. 0. S. Wilkinson on 
his observations of certain physical phenomena in the Hawkesbury beds, which 
would tend further to correlate these beds with the Bacchus-marsh sandstones, 
in which similar phenomena were observed. As Mr. Wilkinson has lately 
published these observations in a paper in the Journal of the Royal Society of 
New South Wales (December 1870), and has favoured me with a copy of the 
same accompanied by a letter, in which again reference is made to the Hawkes¬ 
bury beds, I may, besides from this paper, quote also from his previous letters. 
In a letter dated 30th September 1878, Mr. Wilkinson -wrote thus:—“ I have 
noticed certain deposits in the Hawkesbury series, apparently due to ice action, 
which would seem to confirm your view as to the correlation of that series and 
the Bacchus-mar.sh beds (in which Daintree has described the occurrence of 
glacial deposits) with your Talchirs. Yet it is strange that in the Hawkesbury 
beds we have not found the Ganejamopteris, which is so abundant in the 
Bacchus-mansh and Talchir series.” 
The absence of Gangamopteris would in this case be no objection against a 
correlation of the Bacchus-marsh bed.s and Hawkesbury beds, because the cor¬ 
relation of the Indian Talchirs with the Ekka beds in South Africa and with the 
Permian Breccia in England is also based upon these similar physical phenomena 
only. 
In a subsequent letter dated 25th October 1879, Mr. Wilkinson wrote again 
thus:—“ Recently in company with Dr. von Haast, E.R.S., of New Zealand, 
I again examined the Hawkesbuiy beds, and the Doctor quite coincides with the 
views which I mentioned to you in a former letter, that these bods contain many 
ice-bome boulders.” 
In his recent letter dated 20th July of this year, he again -wi’ites with reference 
to the Hawkesbury beds :—“Your correlation of the Hawkesbury beds with the 
Bacchus-marsh beds is, I think, correct, yet it is very strange that in the former 
wo do not find the Gangamopteris. This, however, may be due to the fact 
that in Victoria the Gangamopteris has only been found near the ancient margin 
or shore-line of the formation where the latter junctions with the Silurian, 
whereas our Hawkesbury fossils were obtained from beds many miles from the 
margin of the foiunation, so that the Gangamopteris may yet be found when 
searched for near the margin.” 
' McCoy : Prodr. Pal. Victoria, Decade II (Gangamopteris). Brough Smyth : Rcijort of Pro¬ 
gress, etc., 1874, p. 34. 
- Mines and Mineral Statistics, etc., 1875, p. 181 et seq. 
