314 THE SEASON WHY. 



" In the mountain of the height of Israel will I plant it ; and it shall bring 

 forth boughs, and bear fruit, and be a goodly cedar : and under it shall dwell all 

 fowl of every wing ; in the shadow of the branches thereof shall they dwell." 



E/5EKIEL XVII. 



7. The narrow zone between 9,000 and 9,200 feet, only produces a few lichens. 

 Icyond which, there is complete sterility. 



' 1241. The Peak of Teneriffe exhibits five botanical districts, thus distinguished 

 by Von Buch : 



1. The region of Africa forms, 1,248 feet, comprising palms, bananas, the 

 sugar-cane, various species of arborescent Euphorbice, Mesembryanthema, the 

 Dracaena, and other plants, whose naked and tortuous trunks, succulent leaves, 

 and bluish-green tints, are distinctive of the vegetation of Africa. 



2. Region of Vines and Cereals, 1,2482,748 feet, comprising also the olive, 

 and the fruit-trees of Europe. 



3. Region of Laurels, 2,748 -4,350 feet, including lauri of four species, the wild 

 olive, an oak, the iron -tree, the arbutus, and other evergreens. The ivy of the 

 Canaries and various twining shrubs cover the trunks of the trees, and nume- 

 rous species of fern occur, with beautiful flowering plants. 



4. Region of the Pines, 4,3506,270, characterised by a vast forest of trees 

 resembling the Scotch fur, intermixed with juniper. 



5. Region of the Retama, 6,27011,061 feet, a species of broom, which forms 

 oases in the midst of a desert of ashes, ornamented with fragrant flowers, and 

 furnishing food to the goats which run wild on the Peak. A few gramineous 

 and cryptogamic plants are observed higher, but the summit is entirely des- 

 titute of vegetation. 



1242. There are many plants which can accommodate themselves to the most 

 diverse climates and localities; and therefore ascend from the plains close to the 

 boundary of vegetable life on the highest mountains. But it is the general law 

 in these cases for such plants to be singularly modified in appearance and 

 anatomical structure as they ascend. The spring gentian, Gentiana verna, 

 is one of the exceptions, which Raymond found unaltered at all heights in the 

 Pyrenees. 



1213. Trees, plants, and bushes, of humbler growth, which occur on the plains 

 and at great heights, are usually much smaller in the latter situation. r i he 

 leaves, and everything green about them, dwindle with the increased elevation ; 

 and the pure, well defined green is exchanged for an ill-defined light yellow. 

 Singular enough, those parts which seem most capable of resisting cold, as tho 

 leaves and stalks, are uniformly subjected to a diminution of their . vital 

 functions; while the flowers remain of the same size, are never deformed, and 

 become more dense and richer in their colours. While the Hyosotis silvestris 

 becomes stunted, its flowers assume an intense blue the-admiration of the 

 traveller. The flowers of the pale primrose have a much deeper colour on the 

 top of the Faulhorn, while the plant itself is much smaller than its congener on 

 tlie Swiss plains. The observations of M. Parrot, among others, are to this 

 effect on the flora of the Caucasus, of Ararat, the Swiss and Italian Alps, and 

 the Pyrenees. The arctic flora ii similarly distinguished. 



1241. The preceding references to different climatic states are, however, 

 perfectly inadequate to explain the phenomena of vegetable distribution. While 

 an analogy is often observable between the plants of different regions under 

 corresponding circumstances of latitude, elevation, and soil, the species are 

 generally found to be different ; and usually the botanical character of countries 



