reefs lying inshore along the North Queensland coast line 

 belong to this more recent phase of Barrier Reef formation. 

 Previous to this land submergence during the Human Period 

 the shoreline of Eastern Australia was a monotonous 

 feature unbroken by inlets and quite unfitted for navigation. 



Black Soil Plains. — These form a great topographic 

 feature which has been determined in great measure by the 

 waste derived from the mountains of the Plateau Period. 

 (Both these and the associated waste slopes of the inland 

 are to form the future granary of Eastern Australia.) 



Earthquakes.— The area in the neighbourhood of the 

 greatest faulting is the scene of mild but frequent earth- 

 quakes. This earthquake zone lies in the Australian Alpine 

 knot and in the Adelaide region. 



<B) Biological Significance. 



The briefest mention only is here made to the relation of 



the geographical distribution of plants to the physiographic 



changes in Eastern Australia, inasmuch as the subject will 



be dealt with at length at a later date by Mr. R. H.Oambage 



Botanists of Eastern Australia have been perplexed over 

 many points in the present geographical distribution and 

 the life histories of plants belonging to this vast region. 

 A few examples of such difficulties may be here presented. 



(1) Variable floras of late and post Tertiary time— This 

 subject has already been discussed under the head of " The 

 Evidence of the Leads." 



(2) The present flora of the coastal area is quite unlike 

 that of the area west of the divide in general appearance, 

 vhereas the flora of the period immediately preceding the 



Kosciusko Period 

 Eastern Australia 



appears tohav i..-«-n fairly uniform "\vr 



