334 C F. LASERON, | 
ocean, for we find its remains scattered almost anywhere 
in marine rocks. No crinoids were found in the district ; 
it is evident that they required much clearer seas, far 
distant from land. The very shallow seas with strong 
currents in which the Nowra Grits were deposited, could 
only support a brachiopod fauna, which evidently stood 
a greater variety of conditions than the pelecypods. I 
have but touched on this most fascinating subject, which 
seems to me of considerable geological value. Further 
data however are required, which can only be gained by 
careful and systematic collecting. 
Conclusion.— While thoroughly conscious of many short- 
comings in the preceding notes, I nevertheless think, that 
they give a fairly complete picture of the conditions which 
prevailed at the close of the period which marked the 
deposition of the Lower Coal Measures, and at the begin- 
ning of the formation of the Upper Marine Series. Though 
these observations were purely local, it seems to me that 
they will probably apply to other localities on the border 
of the old Permo-Carboniferous sea. This class of geo- 
logical work is particularly interesting, dealing as it does 
with an ancient geography which existed millions of years 
ago, and which was superficially different and yet had 
essentially the same features as that which prevails now. 
And consequently, if I have added in these pages but one 
particle to our knowledge of this ancient earth of ours, I 
shall be quite satisfied. 
EXPLANATION OF LETTERED LOCALITIES ON Map. 
. Shales containing Aséartila polita etc. 
Shales containing Zaphrentis. 
Sandstone with abundant Productus. 
SOW > 
. Mudstones and sandstones with abundant and well preserved 
fossils chiefly pelecypods. 
bs 
Sandstone with Goniatites and worm burrows ? 
