70 SUNKLANDS OF PORT PHILLIP BAY AND BASS STRAIT 
the Port Phillip Bay, King Bay, and Bass Strait Sunklands, and 
at different horizons in t& dune accumulations on the Nepean 
Peninsula. King Bay is the name of the triangular portion of 
Bass Strait immediately south of Port Phillip Bay and north of 
a line bearing westerly through Cape Schanck ; it is so defined in 
a sketch of Lieut. James Grant’s chart made by him in 1800, now 
in the historical collection of the Public Library of Victoria, Mel- 
bourne. This restricted application of the name was apparently 
realized by Boys (1935), who states that Grant named “the recess 
in the coast line to the south of Port Phillip Bay, Governor King’s 
Bay.” Grant’s name has since been abbreviated to King Bay. 
The valley of the Yarra and the Tamar Major Rivers during 
the Pleistocene or Ice Age has been reconstructed by connecting 
up the soundings on the Admiralty Charts into bathymetrical 
contour lines. Where the Admiralty has done this, as with the 
10 fathom line in Port Phillip Bay, the sunken river system shows 
up distinctly. Evidence as to the former channels through the 
Nepean Bay Bar was afforded by bores, particularly the Wan- 
naeue and Sorrento Bores. Briefly, before the middle of the 
Pleistocene, the Yarra flowed in a broad valley on a mature land 
surface as far, at least, as Cape Otway, and emptied into the 
Southern Ocean. Since then, due to the subsidence of the land 
surface and recurring rises of sea level, the broad valley and 
most of the higher ground that formed the watersheds have been 
flooded by the waters of the Southern Ocean, and the Yarra has 
emptied into the headwaters of King Bay or Port Phillip Bay. 
This investigation is one in the field of Victorian and Tas- 
manian Pleistocene geology and climatology. It discusses the 
land connections between Victoria and Tasmania during the later 
part of the Pleistocene and the alternation of cool and warm 
climatic periods. On the assumption that the Tasmanian animals 
migrated, for the most pail, from the Australian mainland, and 
some survivors of these migrations are still to be found on the 
Bass Strait islands, certain groups of the fauna and elements of 
the flora will be discussed from the standpoint of the evidence 
available as to the physical aspect of the former land connections. 
Port Phillip Sltneland 
/. Port Phillip SunMand 
Port Phillip Bay is a land-locked bay, with a length of about 
31 miles from north to south and a breadth of 20 miles from east 
to west — it covers an area of about 735 square miles. Its eastern 
and western shores converge northwards, and north of Point 
