ANALYTICAL CLASS-BOOK OF BOTANY. 



second are found elsewhere. Here the gorgeous Passion- 

 flowers, and a thousand parasitic climbers crush the 

 strongest trees in their deadly embrace ; Palms lift their 

 august heads in the serene air ; the graceful Cocoanut 

 ripens its refreshing fruit ; the Banana mellows its 

 luxuriant clusters, and the richness of vegetation is in- 

 conceivable. As this region embraces the Southern 

 Cordillera, it is, in respect to height, marked by several 

 distinct bands of vegetation. In ascending the Andes, 

 in Peru, we meet with the Cinchonas, or medical-bark 

 trees, which, according to Humboldt, is the middle 

 region, and the zone of Whortleberries, the latter marked 

 by many species of Gentian, Sage, Saxifrages, Sedges, 

 several European Grasses, and in the lower parts the 

 Oak and Fir. In Peru, and perhaps also in Mexico, the 

 Potato is indigenous, and is still seen growing wild, 

 appearing to delight in rocky cliffs near the sea. 



533. REGION OF ARBORESCENT COMPOSITES, or of 

 Asters with tree-like stems. This occupies Buenos 

 Ayres and the Eastern temperate regions of South 

 AmeBfca. The Flora of this district agrees in many 

 respects with that of Europe, while it differs greatly 

 from that of the Cape and New Holland ; for the Iris, 

 Geranium, Myrtle, and Protean tribes are either wholly 

 wanting, or very few in number, the distinguishing fea- 

 ture being that which gives its name to the region. 



534. THE ANTARCTIC REGION embraces the countries 

 around the Straits of Magellan. Here the Arctic polar 

 forms re-appear in the numerous Saxifrages, Gentians, 

 and Primroses ; and there is a resemblance to the Floras 

 of the American Highlands and the Cape. 



535. INSTANCES OF PARTIAL DISTRIBUTION not de- 

 pendent on climatic conditions. While the most nu- 

 merous species and tribes of plants, and their allies, are 

 generally distributed in corresponding degrees of climate, 

 or altitude often spreading over whole countries, and 

 disappearing only to reappear in widely severed zones, 

 there are certain species which never transcend the nar- 

 row limits to which they are either by Nature or Habit 

 confined. Thus in a little cluster of Islands, the Mo- 

 luccas, the Clove is found, and nowhere else ; confined 

 to a narrow girdle of the Andes flourish the race of 

 Peruvian-Bark trees ; on three small Islands of Africa 

 the Double Cocoanut tree ; in a little corner of Asia, the 

 Tea shrub ; and almost within the confines of a single 

 mountain, still lives, though in apparent decay, the 



Mention so ino of the characteristic plants. IIow on the Cordillera? What 

 zones mentioned ? By what is each distinguished ? What valuable root na- 

 tive, and of what parts ? Nexteegion what lands does it occupy by what 

 plants distinguished ? With wnat does this F.'ora agree in many points from 

 what ones greatly differ? Next Region what countries embrace? What 



famous Cedar of Lebanon. Are these the remnants of 

 numerous races, which in times past have been widely 

 scattered, and now, like certain races of men, are falling 

 into decay, and disappearing from the Earth? We 

 question the Past ; the long-gone Ages hide themselves 

 in the still deepening shadow, and are silent. We ques- 

 tion the Future ; and the great silence behind seems to 

 vibrate beyond, as if with a kind of dumb echo ; and in 

 the mute answer we gather only this, that in the living 

 Forms of the Present are bound up all the wisdom of the 

 Past, all the knowledge of the Future, so we only study 

 them faithfully, and interpret them truly, by the light 

 we have to-day. 



CHAPTER XXXIII. 



ECONOMICAL USES OF PLANTS. 



536. THE most important plants, and parts of the 

 plant, I will now, briefly as possible, attempt to classify 

 and present to your view, beginning at the Root, and 

 ascending to the Seed. 



USES OF THE ROOT. 



537. For the sake of brevity, and because they are 

 popularly known as such, I have ranked all subterranean 

 parts under the head of Roots in this classification, which 

 is one of mere convenience, and will in nowise contradict 

 the arrangement (238) by which the Bulb, and various 

 other subterranean modifications of the growing axis, are 

 now ranked among Stems. 



538. The nutritive properties of the Root consist 

 chiefly of starch, which is stored away in its receptacles 

 for the support of that second year of growth, which 

 almost all greatly thickened roots are constituted to 

 sustain. 



539. ROOTS AS A SUBSTITUTE FOR BREAD. First in 

 this rank comes the Potato, which was originally a small 

 rank tuber, native of Peru, but is now cultivated, more 

 or less, over the whole civilized world. The Sweet 

 Potato is a Convolvulus, and belongs to the same genus 

 with the common Morning-Glory. It forms a staple 

 article of food in several of the South American coun- 

 tries, especially Guiana. The Manioc root, from which 

 Cassava bread is prepared, is one of the most important 

 articles of food throughout all tropical America ; and 



forms reappear what Floras resemble ? How are the most numerous species 

 and tribes generally distributed how certain species? What tree confined to 

 the Moluccas to a small girdle of the Andes to three small African Islands 

 to Mount Lebanon ? What shrub to China ? What thought suggested ques- 

 tions reflection ? 



