GEOGRAPHICAL UNITY of EASTERN AUSTRALIA 

 in LATE AND POST TERTIARY TIME, with 

 APPLICATIONS to BIOLOGICAL PROBLEMS. 



By E. 0. Andrews, b.a., Department of Mines, Sydney. 



[Read before the Royal Society of N. S. Wales, November 2, 1910.] 

 Table of Contents. 



1. Introduction.— Definition of Geographical Unity. The 

 position of Geology and Geography in Science. The value of 

 analogical method. 



2. Thesis. 



3. General Topography. — Inland area. Plateaus arranged 

 peripherally to continent. Australian Alps, a knot in the south- 

 east angle of the continent. Eastern highlands fall in parallel 

 curving faults and flexes to shoreline. Plateau traversed by pro- 

 found canons, ending in high waterfalls. Shoreline occupied by 

 harbours. Continental shelf narrow. Southern and central por- 

 tions of shelf warped rapidly to ocean depths. Northern portions 

 of shelf warped much more slowly to ocean depths. 



4. More detailed statement of topography. 



(A) The evidence of the ro--r systems.— The Snowy and 

 Hawkesbury. 



<B) The evidence of the "Leads." The recent " Leads." 

 The "Leads" of the " Newer Volcanics." Murray, 

 McCoy, and von Mueller. Flora of leads very 

 different to that of same regions to day. Erosion. 

 Newer Volcanic "Leads" most probably Pliocene. 



5. Significance of observations. 



(A) Physical. — Recent shore line emergence and sub- 



mergence. Rapidity of plateau formation. Con- 

 tinental creep. Curves convex to ocean. Suess' 

 principles. 



(B) Biological.— Peculiarities of present flora of Eastern 



Australia. Isolation by plateau formation. 

 Modification of floras and faunas by isolation. 



