28 K. H. CAMBAGE. 



100 miles away, is formed by the steep mountain chain which 

 averages from 3,000 - 4,000 feet high, and in places reaches 

 6,000 - 7,000 feet. With an annual rainfall of from nearly 

 40 and up to 60 inches from south to north, gorges are being 

 cut into the elevated parts by denudation, and in the deep 

 valleys thus formed, conditions of shelter and moisture 

 combine to produce trees, some of which are amongst the 

 tallest in the world. A feature of the Coastal Area is its 

 humid atmosphere, and this is partly the result of the 

 Kosciusko uplift, which had the effect of shutting off a 

 considerable percentage of ocean moisture and rainfall, 

 which previously would have penetrated much further 

 westward than at present. The result is a drier climate 

 in the Interior towards which the summer heat causes the 

 moisture-laden north east wind to blow, the moist effect of 

 which however is largely intercepted by the eastern face 

 of the mountains, thus increasing the humidity of the 

 Coastal Area. 



It seems undoubted also that the presence of the warm 

 Notonectian current, 1 which flows past the coast of New 

 South Wales, also contributes to this humidity, for it has 

 been noticed that certain plants which avoid the ocean side 

 of the Main Divide in this State, flourish on the southern 

 or ocean side of the prolongation of the same range in 

 Victoria, beyond where the effect of this current reaches. 



It is in this division that the conditions are found which 

 should most nearly approximate those of Miocene time in 

 South Eastern Australia. Nor is evidence wanting that 

 such an assumption has good grounds for support, because 

 it is well known that the Tertiary fossil leaves which have 

 from time to time been discovered in the Mountain Region 

 and on the Western Slopes, resemble those of the present 

 Coastal Area more than those of any other plant-zone. 



1 See Presidential Address by C. Hedley, f.l.s., Proc. Linn. Soc. N. S. 

 Wales, Vol. xxxv, p. 10, (1910). 



