8 THE PROBLEM OF ANTIQUITY OF MAN IN AUSTRALIA 
two types with other races of mankind and with each other? Are 
they mixed or pure races? These are problems for physical 
anthropologists. The few fossil skulls found in Australia have 
Australoid or Tasmanoid characteristics, and there are no fossil 
remains that suggest that the Australian region was ever occupied 
by other types of mankind before the arrival of modern Euro- 
peans. The Australian wild dog, the dingo, was the only large 
terrestrial placental mammal, man excepted, living in the area 
and it is confined to the mainland. What are its affinities with 
other species of dog? Could it have evolved in Australia? If not, 
where did it come from? Did it find its way overland unassisted 
by man or did it come as the domestic dog of human immigrants 
who crossed stretches of sea by canoe? These are problems for 
zoological systematists and palaeogeographers, and the answers 
are of some importance since fossil dingo bones have been found 
associated with remains of extinct marsupials in deposits that 
suggest some geological antiquity. Did the Tasmanians once 
oceupy the mainland of Australia or did they go direct to Tasmania 
from some other locality such as New Caledonia? If they migrated 
from Australia, did they do so by a land-bridge which once 
joined island and mainland, or by canoe after the land-bridge 
disappeared? If they once occupied the mainland and were later 
partly exterminated, partly absorbed by an invasion of Australoid 
migrants, do Australian aborigines retain traces of the racial 
intermixture? Geologists and anatomists can furnish the answers. 
Finally, we must assess the value of evidence for antiquity of 
human bones and artefacts found embedded beneath the surface ; 
it must be based on knowledge of the relative ages of Pleistocene 
and Holocene horizons in Australia and their correlation with 
similar horizons in the northern hemisphere. This is the province 
of geologists. 
The literature on these subjects is widely scattered in books and 
scientific periodicals, and no comprehensive statement of the 
problem of antiquity of man in Australia as it now stands has 
been published. In view of the recent discovery in a river terrace 
at Keilor near Melbourne of the fossil human skull (Pl. 1) which 
is described elsewhere in this volume by Dr. J. Wunderly and 
Dr. Wm. Adam, as well as a second skull and limb bones, an 
attempt is made in the following pages to summarize current 
opinions on the subjects. These are widely divergent, and the 
problems offer an attractive field for further research. 
Many further references to Australian Post-Tertiary geology 
could be added to the bibliography, but those selected will suffice 
for a general survey of the subject. 
