CLIMBING PLANTS. 



709 



Tlie erect stems of tlio Ivj-, adonioil witli cordate shining foliage-leaves wlion 

 treated as slips or cuttings, send absorbent roots into the ground and ramify; 

 but, strangely enough, the shoots which they develop, although they now spring 

 close upon the ground, do not become climbing stems, but exhibit exactly the 

 same stmcture, the same erect position, and the same foliage as the shoots on 

 the top of a wall or on the summit of a tree. Anyone seeing for the first time 



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Fig. 170. — Bignonia argyrO'Violaceti, froiu ilr 



rjo Negro in Brazil. 



such Ivy grown in pots, is tempted to mistake it for some erect tropical Aralia, 

 and even experienced gardeners and botanists may be misled by these jjlants. 

 We are involuntarily reminded by these successive shoot-structures, which differ 

 so much in their outer form and internal construction, of the alternation of 

 generations occurring in Vascular Cryptogams, and so much the more since the 

 climbing shoots which precede the erect flowering shoots do not develop flowers 

 and fruits, and thus to some extent resemble an asexual gener'ation. 



Several Indian species of fig, the stems of which climb up rocky avails and 



