Till 
our ■n'estern districts, as near Molong. Moreover, the almost entire absence 
of any forms of coral life from the Lower Marine Series may, as suggested 
hy Mr. David, have been due to the enormous development of tuffs in the 
Ilhacopteris and Lepidodendron beds which form the upper portion of the 
l)receding formation. Then, again, though the occurrence of striated boulders 
in the conglomerates of the Upper Marine Series points to deposition in 
which ice action has been concerned, the comparative abundance of certain 
genera of corals in several horizons in the Series is evidence of the sea at the 
time having been comparatively warm, and is opposed to any theory as to a 
general refrigeration of the Antarctic Ocean in this part of the Permo- 
Carboniferous Period. 
The accomjmnying table of classification of the different series of the 
Permo-Carhoniferous must to some extent he considered as provisional, and 
thus indicates how large a field awaits systematic geological survey and 
palmontological investigation. 
I have the honour to he, 
Sir, 
Your obedient servant, 
C. S. WILKINSON, 
Geological Survcyor-in-Charge. 
IIarrie Wood, Esq., J.P., 
Under Secretary for Mines. 
