238 MISSOURI BOTANICAL GARDEN. 



it would hardly have been possible to gain any numerical 

 idea of the relative frequency of the various forms as com- 

 pared with the other members of the floras. These modi- 

 fications have seemed perfectly justifiable in view of the 

 purpose which the regions are to serve. 

 The divisions have been limited as follows: 



I. TROPICAL REGIONS. 



1. Tropical African Region. Arabia and the continent of 



Africa south of the Tropic of Cancer to Cape Colony, South 

 Bechuanaland, South African Republic, BasutoLand, and Cape 

 Colony; also Sokotra Island. 



2. East African Island Region, a, Madagascar; b, Mas- 



carine Islands andRodrigues; c, Seychelles Islands. 



3. Indian Region. Western and eastern peninsulas of India and 



all islands lying between 17° N. lat. and the Tropic of Capri- 

 corn. 



4. Tropical American Region, a, Brazil, Uruguay, Ecuador; 



b, Guiana, Venezuela, Colombia, Central America; c, Antilles 

 and Bahamas; d, Mexico and Southern California. 



II. AUSTRAL REGIONS. 



5. South African Region. Continental South Africa south of 



the tropical region, and the island of St. Helena. 



6. Australian Region. Australia and Tasmania. 



7. Austral American Region. Argentina, Chile, Patagonia and 



Tierra del Fuego. 



8. New Zealand Region. The island. 



9. Antarctic Region. Land masses lying south of the above 



austral regions. 



III. BOREAL REGIONS. 



10. Mediterranean-Oriental Region. The Atlantic Islands (Ca- 



naries to Azores), Africa and Arabia north of the tropical 

 region (Tropic of Cancer), Spain, Italy, Turkey in Europe 

 and Asia, Transcaucasia, Persia, Baluchistan, Afghanistan, 

 and the lands included by the outer limits of these. 



11. Central Asian Region. Turkestan, Mongolia and Tibet. 



12. East Asian Region. China, Manchuria, Korea, and Japan 



except Sakhalin Island. 



13. Central North American Region. Roughly commensurate 



with the United States. 



14. Northern Region. Land masses of Europe, Asia and America 



above the limits of the four boreal subtropical regions 

 described above. 



