INTRODUCTION. XX1X 
briefly defines, and then proceeds to divide the vegetation of the earth into “ kingdoms, 
regions, provinces, zones, and districts.” To give the whole of his subdivisions would 
occupy more space than can be afforded, and carry us beyond what is necessary in this 
discussion. His primary divisions are four, corresponding to his four Tertiary elements. 
These are :—the northern extratropical floral kingdom, the paleotropical floral kingdom, 
the South-American floral kingdom, and the old oceanic floral kingdom. In conformity 
with English usage we will call his primary divisions regions and the secondary ones 
subregions ; and where we have occasion to refer to the smaller divisions, the names 
given above will be employed. Engler’s secondary divisions are as follows :— 
1. NoRTHERN EXTRATROPICAL REGION. 
SuBREGIONS: 1. Arctic; 2. Subarctic or Conifer; 3. Central Asiatic; 4. Mediter- 
ranean; 5. Mandshurian and Japanese; 6. North-American Pacific; 7. North-Ame- 
rican Atlantic. 
2. PaLZoTRoPIC REGION. 
SuBREGIONS: 1. West-African forest ; 2. African and Arabian desert; 3. Malagassy ; 
4. Western Indian; 5. Tropical Himalayan; 6. East-Asiatic; 7. Malayan; 8. Arau- 
caria; 9. Polynesian ; 10. Sandwich Island. 
3. SouTtH-AMERICAN REGION. 
Susreeions: 1. Mexican Highlands; 2. Tropical American; 3. Andine; 4. Gala- 
pagos ; 5. Juan Fernandez. 
4, Otp Ocranic REGION. 
Suprecions: 1. Antarctic forest of South America ; 2. New-Zealand; 3. Australian; | 
4. Kerguelen; 5. Amsterdam Island; 6. Cape; 7. Tristan d’Acunha; 8. St. Helena. 
The ternary subdivisions or provinces of the Northern Extratropical Region of the 
above scheme are about forty; many of them are divided into several zones, and some 
of them again into numerous districts. Subdivision is, for obvious reasons, not carried 
so far in the three other regions. 
I have already put on record * my objections to that part of Dr. Engler’s scheme 
relating to oceanic islands and the “antarctic” Flora; but I have now to deal 
with it as a whole. Theoretically there may be much to justify his regions; yet it 
seems to me that any attempt at division based partly upon assumed, or even proved, 
anterior conditions, and partly on present conditions, is unsatisfactory and confusing. 
On this point Wallace says + :—‘ Our object is to represent as nearly as possible the 
* Botany of the ‘ Challenger’ Expedition, i. Introduction, p, 50. 
ft The Geographical Distribution of Animals, i. p. 55. 
