CHAPTER V 



CLIMBING PLANTS 



MR REID also attributes "use" to climbing 

 by " tendrils " ; but this is only one of an infinite 

 variety of uses which plants have acquired. The 

 same word is applicable to the ivy which climbs 

 by roots on the stem against a wall or trunk 

 of a tree, etc. ; to the Clematis which " uses " 

 the sensitive petioles or leaf-stalks for the same 

 purpose ; to the pea, which has converted many 

 of its leaflets into tendrils ; to the Virginia 

 creeper and others which have superadded 

 adhesive pads to the tips of the tendrils. These 

 latter are not foliar but metamorphosed flower- 

 ing branches. Again, a vast number of tropical 

 lianes and temperate plants climb by their 

 stems, as the hop, scarlet-runner and Convolvulus 

 of this country. These all have peculiar 

 structures which, like their properties, have 

 been " acquired " and are now hereditary " uses." 

 Corresponding with the external forms there is 

 always specialised internal anatomical structures 

 in each case. These latter originally only arise 

 when the special responsive action takes place, 



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