Chap. II] 



REGIONS OF VEGETATION 



70,1 



ii. THE FEATURES OF ALPINE PLANTS. 

 The characteristic traits of alpine plants can be demonstrated best in 

 species which also occur in the lowlands. The individuals growing in the 

 alpine region have shorter axes, smaller leaves, more strongly developed 

 roots, equally large or somewhat larger, and frequently rather more deeply- 

 coloured flowers, and their general structure is xerophilous. 



Apart from this we can, as a rule, distinguish the following types : — 

 i. El fin-tree. This is characterized by a short, gnarled, often oblique or 

 horizontal stem, and long serpentine branches, which are bent in all direc- 

 tions. The mountain pine, Pinus montana, var. Pumilio, alone represents 

 this type in European moun- 

 tains. The same habit, how- 

 ever, as more recent observa- 

 tions have shown, is assumed 

 by many tropical trees in alpine 

 regions. 



2. Alpine shrubs (Figs. 407, 

 408) have sometimes an upright 

 growth, and are not then essen- 

 tially distinct in habit from 

 lowland shrubs. In the highest 

 belts of vegetation, however, 

 they assume the form of creep- 

 ing, dwarf-shrubs with richly- 

 developed root-system and 

 richly-branched horizontal axes, 

 which spread over the ground 

 or just below its surface. Like 

 elfin-trees, the shrubs are nearly 

 always evergreen. 



3. The type of cushion- 

 plants (Fig. 409), which, except 



in the case of mosses, occurs ^ ., . fl f ,, , ■, c , , f f , 



Mc 407. Alpine flora of toe Andes. Shrubs of the 



in the lowlands only in islands paramos. 1. Hinterhubera ericoides (Compositae). 



e ., ,, Venezuela. 2. Senecio vaccinioides. New Grenada. 



of the south temperate zones Natural size _ After Wed dell. 

 and of the arctic district, is 



represented in the alpine region of mountains of higher latitudes in both 

 hemispheres, and in the Andes, by a multitude of forms of the most 

 diverse affinity. In such a cushion-plant, the members of an axial system, 

 the main axis of which is sometimes still present, sometimes dead, are 

 so compacted together that they touch one another on all sides, and dis- 

 play leaves and flowers only on their free surface. The size of the cushion 

 varies greatly. In certain species of Androsace and Saxifraga in the 



SCHIMPER 2 Z 



1 JJ+***- 



