Jan., 1923] 
CAMPBELL-AUSTRALASIAN BOTANICAL NOTES 
39 
nevertheless there is sufficient resemblance throughout to indicate former 
land connections between the different regions in earlier geologic time. 
Australia comprises an area slightly greater than that of the United 
States exclusive of Alaska. Compared to the United States, however, it 
shows much less variety in its topography. 
The southernmost point of Australia proper scarcely reaches the fortieth 
parallel, and Tasmania is only a little south of this. Hence the southern¬ 
most districts have a warm temperate climate, while more than a third of 
the continent lies to the north of the tropic of Capricorn, and has a tropical 
climate. The climate, as a whole, has a distinctly continental character, 
with great range of temperature, especially in the extensive arid central 
regions. 
The principal mountains are in the extreme eastern part of the country, 
in some places actually on the coast. This eastern mountain region, the 
eastern highlands, has an abundant rainfall on the coastal side, and it is in 
this region that the most luxuriant vegetation is encountered. This 
mountainous country extends from Cape York, the extreme northern part 
of Australia, along the eastern borders of Queensland and New South Wales, 
and ends in Victoria. The highest mountain is Mt. Kosciusko, near the 
borders of New South Wales and Victoria. This is only a little over 7000 
feet in height, and next to this are the Bellenden-Ker mountains of northeast 
Queensland, rising to something over 5000 feet elevation. The rainiest 
region of Australia is in the immediate vicinity of the Bellenden-Ker range, 
some stations having an annual rainfall of upwards of 150 inches. The 
writer. visited one of these—Babinda, in August, 1921, where there was a 
practical demonstration that this is really a rainy district. Already over 
200 inches had fallen since the first of the year, and it is safe to say that 
this was materially added to during his stay of three days. The precipi¬ 
tation falls off rapidly inland, and a large part of the interior receives less 
than ten inches annually. 
While the rainfall is perhaps the most important element in determining 
the character of the vegetation, the nature of the soil also plays an important 
role. This is especially marked in the tropical and subtropical forests of 
the eastern coastal districts, where the tropical rain-forest types are mainly 
restricted to the rich basaltic or alluvial soils, while the Eucalyptus forest 
is almost confined to sandy soils. 
A second region of relatively heavy rainfall is met with in the extreme 
southwest, where there is a heavy forest growth, but almost exclusively 
of Eucalyptus. 
The plants of Australia fall into three distinct categories. The first of 
these includes a large number of species, mainly restricted to the coastal 
areas of Queensland and New South Wales, which are either identical with, 
or closely related to, Indo-Malayan species. The second, and much the 
largest, group is made up of the peculiar types which are strictly Australian 
