192 
SOUTHERN TEMPERATE ZONE 
Patagonia (and a corresponding belt in the Andes), Ker- 
guelen Island, a belt in the mountains of Tasmania and 
New Zealand, and the antarctic lands and islands. The 
vegetative period is interrupted by more or less of winter 
about July, and in the northern parts there is more or less 
drought in summer. In Valdivia, Victoria, Tasmania, and 
part of New Zealand, where there is plenty of rain at all 
times of the year, there are forests of evergreen and 
deciduous trees with many Conifers. In Paraguay, Natal 
and eastern Australia, the forests contain few Conifers ; the 
evergreen trees are mostly much branched. Other areas, 
eg. in Chili, S.E. Cape Colony, and parts of Australia, are 
covered by a ‘ scrub 5 or 1 bush 9 of evergreen shrubs and 
small trees, usually of pronounced xerophytic character. 
The Pampas, the Kalahari desert and much of Australia are 
covered with a turf of grasses and other xerophytic herbs, 
which becomes very parched in the dry season. 
VI. Southern cold zone \ This includes the areas 
mentioned by name at the beginning of the last paragraph. 
The vegetation is like that of zone I. — undershrubs, herbs, 
mosses, lichens, &c. 
Floral regions 2 . In the earlier periods of the earth’s 
history the climatic conditions appear to have been very 
uniform, and the various plants that then existed appear to 
have had almost universal distribution. This was facilitated 
by their spores being light and easily carried by wind to 
great distances (the Cryptogams are the most widely distri- 
buted of existing species). Towards the end of the secondary 
period the boundaries between the different regions of the 
earth appear to have become more clearly marked, and with 
them the climatic differences. At the same time the seed- 
plants, with their less perfect means of dispersal, arose and 
the flora of the different regions thus became gradually 
different, the new plants evolved in various districts being 
checked in their spread over the globe by the various agents 
discussed above. This process continuing, it has gradually 
come about that at present the floras of different regions of 
the earth’s surface differ very much in their composition, 
though they may agree in their general ecological characters ; 
1 Schimper, Hooker, &c., op. cit. 
2 Cf. Drude, op. cit. and other works mentioned above. 
