ZONES OP ALP1XE VEGETATION. 585 



and is conspicuous for its shrubby Composite. In Madeira, it embraces 

 Kuhl's regions of Spartium and Heath. On the mountains of Lapland, it 

 attains 1,000 feet, and is characterized by Betula nana, Vaccinium, and 

 Salix. In Finmark, its limits are 1,100. 



4. Kegion of Grasses. These predominate in certain Alpine situations, and in 



certain parallels of latitude. In South Shetland, none of the islands exhi- 

 bit any Phanerogamous vegetation, with the exception of straggling grass. 

 In Melville Island, 75 north latitude, the proportion of Grasses to Phaner- 

 ogamous plants is 1 to 5 ; in Great Britain, 1 to 12. In the Andes, the 

 region is traced to Paramos, and occupies a space of 13,000 to 14,500 feet; 

 here are large cattle farms. In the Himalaya, a fine green sward is often 

 seen at 14,600 feet. In Teneriffe, it is distinguished by Humboldt. On 

 the Swiss Alps, Poa annua exists at an elevation of 7,400 feet. 



5. Region of Cryptogamous plants. This is well marked in many places. 



Colonel Hall, in Chimboraco, under the equator, at nearly 16,000 feet, 

 found Draba arctoides, and Culcitium rufescens ; still higher, a moss, which 

 may be considered as having attained the highest limit on the globe at 

 which vegetable life exists. Lichens are the latest plants met with in 

 ascending Teneriffe, the Himalaya mountains, and the Alps. 



1162. In the mountains of the torrid zone, the following regions 

 are described by Meyen, corresponding to the zones given in his hori- 

 zontal range of vegetation : 



1. The region of Palms and Bananas, extending from the level of the sea to 



1,900 feet of altitude. It corresponds to the Equatorial zone. 



2. Eegion of Tree Ferns, and species of Ficus, extending from 1,900 feet to 



3,800. (Tropical zone.) 



3. Region of Myrtacese and Lauracese, extending from 3,800 to 5,700 feet. (Sub- 

 tropical zone.) 



4. Region of Evergreen Dicotyledonous trees, extending from 5,700 to 7,600 



feet. (Warm Temperate zone.) 



5. Region of Deciduous Dicotyledonous trees, extending from 7,900 to 9,500 



feet. (Cold Temperate zone. ) 



6. Region of Abietineas, the Pine and Fir, extending from 9,500 to 11,400 feet. 



(Subarctic zone. ) 



7. Region of Rhododendrons, extending from 11,400 to 13,300 feet. (Arctic 



zone.) 



8. Region of Alpine plants and Lichens, extending from the upper limit of 



shrubs to the snow line at 15,200 feet. (Polar zone.)* 



1163. Distribution of Plants in Britain. The climate of Britain is 

 influenced by its geographical position, and the form and elevation 

 of its surface. The eastern coasts partake more of the continental 

 climate, while the western experience the insular or more equable 

 climate. The mean temperature varies from 45 to 51 F. In 

 ascending the mountains, there is a fall of 1 of the thermometer on 

 an average for every 230 or 240 feet of ascent. The number of 

 Phanerogamous plants amounts to nearly 1600, of Cryptogamous to 

 about 4,800. Mr. H. C. Watson, who is our chief authority on the 



ston, a cheap quarto edition of which is now in the course of publication. 



