306 E. J. STATHAM. 
its shell. These shells which have been fired are easily distinguish- 
able, and are more susceptible of atmospheric influence, becoming 
brittle. Never in any modern instance can it be seen that stones 
have been used in opening them. 
On the Clarence River one of the most extensive deposits is at 
the mouth of the South Channel on the Yamba side, where it is 
several acres in extent, and from three to five feet above high 
water, being generally level, and may be the result of elevatory 
movement. At the mouth of the Oyster Channel, or Woolowuya 
Estuary on the other hand, there are long mounds, on the Yamba 
or mainland side, and on the Micalo Island side extensive terraces 
almost entirely of shell, with occasional water-worn boulders and 
chips of stone, with abundance of estuarine shells other than 
oysters. These deposits have a remarkably artificial appearance, 
so much so that no one for a moment seems to doubt their origin 
as being due to the aborigines, though it seems remarkable that 
the deposit, especially on the Yamba side, extends deeper than 
low-water, and that the shells show no trace of damage by fire or 
otherwise ; the delicate edges being intact and the substance of 
the shell strong and well preserved. 
The occurrence of shell strata all along the East and South 
Coasts of Australia at elevations distinctly above tidal influence, 
the shells being of recent type and frequently differing from those 
at present to be found on the contiguous beaches, is well worth 
careful study. Much of the coast country consists of flat sandy 
or loamy heath with sand-dunes super-imposed, and forming a 
narrow fringe along the coast line. J have noticed in many places 
where the underlying stratum has been exposed along the beach, 
that these shell-layers are existent, and that they are traceable as 
extending under the sand-dunes, and are distinctly referable to 
the flat formation above mentioned on which the sand-dunes are 
an encroachment. These layers are to be found at levels usually 
from four to ten feet above high water, and are important as 
indicating that the Hast and South Coasts (if not the whole insular 
mass of Australia) are rising, further support to which conclusion 
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