xiii 



to give absolute percentages. But the subjoined table, 

 which may be taken as approximately accurate, will, it is 

 hoped, be useful both in itself and for comparison with 

 Mr. Baker's table, which remains of great historical 

 interest : 



Arctic Zone *4 per cent. 



Europe 2'5 



Temperate Asia, including the 



Himalayas above 8,000 ft. ... 25'5 



North Africa, Canary Is -8 



Temperate N. America 3*2 



Temperate S. Africa ... .. 4*5 



Australia and New Zealand ... 6*9 



Polynesia 10'8 



Temperate S. America ... ... 2*7 



Tropical Africa and Mascarene Is. 15'2 



Tropical Asia 34-8 



Tropical America 46*4 



D. P. 

 Kew. March, 1906. 



23941 



