272 R. H. CAMBAGE. 
Tableland with an elevation of about 1,000 feet, at a dis- 
tance of 150 miles from the Gulf, and this forms some of 
the highest land in Northern Australia, excepting a few 
isolated peaks, and also the Main Divide along the Cape 
York peninsula, 
From observations made throughout Eastern Australia 
in regard to the effect of the mountain chain upon the 
climate and vegetation, and a comparison between eastern 
and northern conditions, it would appear that the absence 
of brush or jungle from Northern Australia is largely owing 
to the absence of any considerable rainfall for about seven 
or eight months of the year, viz., from March or April tilk 
December, and this dry period would be greatly reduced by 
the presence of a mountain range upwards of 3,000 feet 
high and within 100 miles of the coast line. Under present 
conditions there is no cold zone such as would be formed 
along a high mountain chain, and which would create con- 
ditions of moisture throughout the year, and induce more 
dense growths. 
During the wet season, and with the monsoonal influence, 
the rainfall along the southern shores of the Gulf of Car- 
pentaria aggregates about twenty inches in the months of 
January, February and March, but this amount is much 
exceeded around Cairns, on the steep eastern face of the 
Main Divide, where the records show an average of about 
twenty inches for each of those months mentioned. The 
clouds, which are borne across North-eastern Australia by 
the south east trade winds, precipitate the rain as they 
ascend the eastern face of the mountains, and afterwards 
reach the interior as descending clouds. 
Briefly, the conditions necessary for the production of a 
‘*‘prush’’ flora are a good rainfall, warmth, shelter from 
cold winds, and a basic rather than a siliceous geological 
formation. With an abundance of moisture, warmth, and 
