272 GEOGRArHY OF PLANTS. 



which springs towards tlie pole. As yet we know only, 

 from Humboldt's immortal labours, the vegetation upon the 

 highest chains of the Andes, in South America; for the 

 Floras of the much higher mountains in Noithern India, 

 which are called the Himalaya Mountains, and of the Moun- 

 tains of the Moon, in Africa, are entirely unknown to us. 

 The Flora of tlie Andes, at the height of 14,760 feet, is al- 

 most entirely of a peculiar kind ; and if a pair of Ranunculi, 

 a Gentiana, and a Bihes^ remind us of the Flora of" the poles, 

 the remaining productions are completely peculiar, and prove 

 that the height above the level of the sea is very far from 

 producing universally the same forms. Yet we must add, 

 that in Europe, at least, many northern and even polar forms 

 appear under the snow-line of the Pyrenean and Helvetian 

 Alps. Of this the Dwarf Willow, Dwarf Birch, Saxifrages, 

 Ranunculi, Cerastia, and other genera, are striking proofs. 



Of perfect plants, the Daplme Cneorum seems in Europe 

 to hold the most elevated station, since, on Mont Blanc, it 

 stands at 10,680 feet ; and, on Mont Perdu, at 9036 feet 

 high. The growth of woody plants ceases, on the Alps of 

 central Europe, at the height of 5000 feet ; and, on the Rie- 

 sengebirge, at 3800. Oats grow on the Southern Alps at 

 3300, and on the Northern scarcely at 1800 feet. The Fir 

 grows on Sulitelma, in Lapland (68 degrees N. Lat.), scarce- 

 ly at the height of 600, and the Birch scarcely at the height 

 of 1200 feet. On the other hand, upon the Alps which 

 divide Italy from France and Switzerland, Oaks and Birches 

 grow at 3600, Firs at 4800 ; and the same plants grow on 

 the Pyrenees above the height of 600 feet. 



In Mexico, the mountain chains, and, in particular, the 

 Nevado of Toluca, are covered, above 12,000 feet high, with 

 the occidental Pine {Pinus occidentalis) ; and, above 9000 

 feet, with the Mexican Oak {Queirus Mexicnna, spicata) ; 

 as also with the Alder of Jorullo {Alnus Jomllcnsls.) 



On the Andes, Palms grow at the height of 3000 feet. 

 The woody Ferns, {Cyathea speciosa, Menlscmm arhoj^cscenSy 

 J.spid'wm rostrahim)^ are found as high as 6600 feet ; as are 

 also the popper species, Melastomea',Cinchonye, Dorsteniae,and 



