ORGANS OF GROWTH. 



23 



joined end to end, as in several species of cactus, Kleinia, 

 and mistletoe ; or of round knobs, like turnip radishes, 

 joined together, as in Euphorbia globosa. 



Some plants growing in hot, dry places in South 

 Africa, have stems and branches more like petrified 

 objects, or coral, than living plants — Geranium Bur- 

 mannii being an example — and may be compared to 

 pieces of light-green wax candles stuck together in an 

 irregular manner. Colletia horrida, a hardy garden shrub, 

 is a singular example of a stem being winged, consisting 

 of woody triangular opposite lobes, alternating at right 

 angles to each other. But the most remarkable plant 

 stem of recent discovery is that of Welwitschia mira- 

 hilis, which with many of the preceding will be specially 

 noticed under their respective families. 



In the cactus family, and many trees and herbs, the 

 stems are often flat and contorted in a crested manner, like 

 the garden cockscomb, all such growths being viewed as 

 monstrosities, and to which the term fasciated is applied. 



Branches. (Lat. ramiy Gk. cladus.) 



Branches are lateral multiplications of the main stem ; 

 their nature, relative position to each other, and angles 

 of divergence impart to trees special aspects or phases 

 which are generally very uniform to all trees of the same 

 species growing under similar influences. Their direc- 

 tion varies from erect to horizontal and pendulous, as in 

 the weeping willow and birch. In firs and araucarias they 

 are produced in whorls, some forming a right angle with 

 the stem. In Dammara and some species of Podocarpus 

 they are deciduous, falling away, and leaving a clear 

 scar or mark, giving the character of being attached to 

 the stem by a joint. 



