674 GEOGRAPHICAL AND GEOLOGICAL BOTANY. 



temperate zones rise to 14,000 feet j that of the Himalayas to 18,000 feet 

 in the northern parts. Our data scarcely suffice for the illustration of 

 these modified conditions, and therefore we have confined ourselves to a 

 limited number of the best-explored mountain-regions of the Old and New 

 Worlds. 



We now give a brief sketch of the characteristics of the different 

 regions of altitude, as classified by Meyen. 



1. Region of Palms and Bananas. Corresponding to the equatorial 

 zone, and already characterized under that head, p. 669. 



2. Region of Tree-Ferns and Figs. Corresponding to the tropical zone, 

 p. 670. The genus Ficus is most prevalent in the elevated forests of the 

 equatorial zone of the East Indies, giving them a remarkable character 

 of gloomy grandeur and impervious density. 



8. Region of Laurels and Myrtles. Corresponding to the subtropical 

 zone, p. 670. 



4. Region of Evergreen Trees. Corresponding to the warm-temperate 

 zone, p. 670. 



5. Region of Deciduous Trees. Corresponding to the cold temperate 

 zone, p. 671 ; but this region seems to be absent from the mountains in 

 many parts of the tropical and equatorial zones, since the tree-limit is 

 carried down by peculiarities of climate, which, on the other hand, favour 

 the advance of more southern forms into the upper regions. In Java and 

 Sumatra, stunted trees of the class belonging here replace the dwarf 

 Conifers of European mountains, and form the tree-limit far below the 

 altitude at which forests of tall Conifers occur in the more northern 

 Himalayas, a condition explained in some degree by the local circum- 

 stances of the equatorial mountains, which are deficient in the supplies of 

 moisture furnished by the vast masses of snow resting perpetually upon 

 the Himalayas. 



6. Region of Conifers. Corresponding to the subarctic zone, p. 671. 

 This zone, characterized by the growth of Pines and Firs, is well repre- 

 sented on most mountains, with the exception of the Peruvian Cordilleras, 

 where the Escallonieae are said to be substituted for them. But the Conifers 

 do not always form the uppermost belt of trees, even when they flourish in 

 a well-defined region. Thus the region of the Conifers, in a general 

 sense, which reaches to the tree-limit with Pines in the Alps, Pyrenees, 

 and the Andes of Mexico, includes, in the Scandinavian mountains, in the 

 Himalayas, and the Caucasus, a region of Birches, which rise out of it to 

 form the last representatives of arboreal vegetation. 



7. Region of Alpine Shrubs or of Rhododendra. This region corre- 

 sponds to the Arctic zone, p . 672. In the Himalayas, dwarf Willows, Juni- 

 pers, and species of Ribes or Current seem to represent the vegetation of this 

 region ; while on the Andes of Quito the genus Befaria appears to cor- 

 respond in its geographical development to the Rhododendra of the north. 



8. Region of Alpine Herbs. Corresponding to the polar zone, p. 672, 

 usually presenting only patches of vegetation scattered over a broken surface 

 of ground, covered during the greater part of the year with snow, and ex- 

 hibiting accumulations in all seasons in sheltered spots. Lichens abound 

 here ; Lecidea geographica has been found in most diverse localities where 

 bare rock rises above the ground, forming generally the last trace of vege- 

 tation. The plants of this region are remarkable in many respects, in 



