30 
POPULATION 
resembles a small monkey, and is elsewhere found only in Africa, and 
there chiefly in Madagascar. 
Many varieties of_oxen, deer, antelopes, and sheep, occur in this pro- 
vince, and some of the most useful animals of draught are the Indian 
buffaloes and humped cattle. _The region is also very rich in birds and 
reptiles, possessing, among many varieties of snakes, the dreaded cobra. 
The Ethiopian Province.—Arabia, which is the only part of Asia 
that falls within this area, has a fauna which resembles that of the Sahara, 
and is characterized by such large animals as the lion, the one-humped 
camel, and many kinds of antelopes. 
The Australian Province.— The division between this province 
and the Oriental was first determined by the naturalist Wallace, who con- 
sidered it should be drawn between the Isles of Bali:and Lombok, east 
of Java, and between Borneo and Celebes further north. Since then 
some zoologists, as Sclater, have shifted. this. line to the east of Celebes. 
As a matter of fact, the fauna along the border belt is naturally 
somewhat mixed, and those mammals which are most typical of the 
Australian province nowhere occur on the islands geographically included 
ın Asla. 
POPULATION. 
The distribution of population is conditioned by the following cireum- 
sfances * 
1. Climate.—A comparison between the map on p. 31, showing the 
density of population, and that on p. 23, giving the annual rainfall, will 
indicate how closely the former reflects the influence of the latter. About 
eleven-twelfths of the total population of the continent is concentrated 
in the Monsoon area, which enjoys not only a good rainfall, but also high 
summer temperatures, Both the cold deserts of the north and the dry 
deserts of the interior are only sparsely populated, and mainly by nomadie 
tribes, Some regions of inadequate rainfall can, however, be rendered 
habitable by means of irrigation ; and this accounts for the number of 
towns in Mesopotamia, East and West Turkistan, and Persia. In these 
parts population could be increased by improved irrigation works; but 
still a limit is fixed to the possible density of population by the limited 
supply of water available for irrigation. 
2. Relief of the Land.—This aflects the population directly, 
as rendering some parts less accessible than others, and indirectly, as