PRESIDENTIAL ADDRESS. 27 



which are chiefly the result of climatic effect, were much 

 less pronounced than is the case at the present day. Having 

 in view that the earth movement was gradual, a conse- 

 quential result would have been that many plants would 

 have responded to the various changes and accommodated 

 themselves to the new conditions. But it does not follow 

 that all would have succeeded in so doing, and amongst 

 the successful ones there should be examples of varying 

 degrees of success to be met with at the present day. Those 

 Eucalypts which survived the great uplift had subsequently 

 to endure a period of greater refrigeration than any tbey 

 had previously encountered, and it is the resultant modified 

 forms which constitute so much of the present Australian 

 flora. The characters adapted or constituents formed for 

 purposes of preservation towards the close of the glacial 

 period, would be likely to remain fairly constant in the 

 various plant-zones, so far as climatic effect is concerned, 

 to the present time. 



Climatic Divisions. 

 Having very briefly outlined the great causes which 

 acted as forces in regulating the changes and development 

 of the flora of South Eastern Australia, it will now be 

 instructive to examine some of the effects. 



At least three distinct type-areas of vegetation have 

 been produced, viz.: — the Coastal or semi-jungle, the 

 Mountain or cold-type, and the Interior or semi-arid ; and 

 owing to physiographic considerations a fourth, which in a 

 previous paper I have referred to as the Western Slopes, 

 may be added. 1 



Coastal Area. — The features of the Coastal Area may 

 be described by saying that its eastern side is flanked by 

 the ocean, while its western boundary, ranging from 35- 



1 " Climatic and Geological Influence on the Flora of N, S. Wales," by 

 E. H. Cambage, Report Aust. Assoc. Adv. of Science, Vol. xi, p. 476, (1907). 



