9270 R. H. CAMBAGE. 
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Our good coastal rainfall is largely due therefore to the 
comparative proximity of the Main Range to the ocean, to 
the height of the plateau (averaging from 3,000.to 4,000 
feet), and the steepness of its eastern face. 
Another effect of this long north and south range is that 
it tends to keep the western country dry, by shutting off 
coastal moisture, and thus is produced the two well known 
distinctive types of coastal and inland floras, the one result- 
ing from moist and temperate surroundings, and the other 
from colder winter and hotter summer conditions. The 
plateau itself, owing to its altitude, produces a third type 
of vegetation, in which is to be found much of what is 
known as the Antarctic element, and it is along this high 
Jjand that many southern plants are able to make their way 
northwards into latitudes which at lower levels are 
altogether too hot for them. KHspecially is this the case in 
connection with the genus Eucalyptus, and the only portion 
of northern New South Wales in which Tasmanian members 
of this genus are to be found is on and, around the New 
Hngland tableland. 
The effect of the two distinct climates produced by this 
Great Dividing Range is so pronounced that although there 
is a dense brush vegetation on very many portions of the 
eastern face, the moment the summit of the plateau is 
reached and drier western, and colder winter conditions 
are encountered, while coastal humidity is shut off, the 
jungle or brush ceases, and its place is taken by open forest 
country, or by low scrub made up of species distinct from 
those on the eastern face. This applies practically through-— 
out the whole length of the range, for at Milton, in the 
south, in latitude 35}°, where the most southern trees grow 
of that northern hemisphere species, Cedrela toona (Red 
Oedar) the brush vegetation may be found in the coastal 
belt, while on the plateau to the west, from Braidwood to 
