232 SYSTEMATIC BOTANY. 



Region of Corresponds to Contains also 



,, , „ „ ' „ ( Enphorbias, Cacti, Magnolias, 



MVKT1.ES AND LaureiS...Sub-Tkopical Zohb... J Heaths, Zinnia, Cycas, Tim- 



(, ber Trees, and a few Palms. 



Evergreen Trees Warm Temperate.... / P,'& Orange, Pomegranate, 



I Vine, Cislus, Smilax, etc. 



Decidtows Trees. Cold Tehfsratb. / Oais, Ash, Beech, Chestnut, 



I Walnut, Conijeree. 



P>HES „ Sub-Arctic. J willow. Birch, 



(^ Poplar. 



I Rhododendron, Azaleas, An- 

 dromeda, Pinus sylvestris, 

 Abies excelsa. Dwarfed Wil- 

 low, A}der, and Birch, many 

 Lichens. 



, _ -n r, r Saxifraga, Drias, Juncus. 



Alpine Plants Polar Zone.... J No tre4, no shrubs, nor culti- 



\ vable esculent plants. 



197. Later study of the Tloras of the different countries 

 has resulted in the establishment of Botanical Provinces, 

 based on the principle that each should " contain one-half 

 the species and one-fourth the genera of some one or more 

 natural families, and individual orders be peculiar to or 

 reach their maximum in the region." In accordance with 

 this, the following partial list may be indicated : 



1. All the land within the Polar Circle and the two con- 

 tinents down to the zone of trees : Its characteristic plants 

 are the Saxifrages and Mosses. There are also many 

 GentianacecB, CarophyUaceoB, Oyperaeem, and SalicacecB. 



2. Europe and Asia, down to the Pyrenees, Alps, Bal- 

 kan, Caucasus, and Altai mountains : The Umbelliferae 

 and Cruciferae characterize this province. Besides these 

 the ComposiUB, Hanuncvlacece, Amentacece, Cariees, and 

 Fungi are largely represented. 



3. Mediterranean region : The Labiatae and Caryo- 

 phyllaceae here abound in great numbers. Eice, Cotton, 

 Millet, Almond, etc., are cultivated. 



