MORPHOLOGY 



same branches that bear normal ones. 



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For example, 



the hard brown scales which surround and protect the 

 delicate foliage leaves in the bud are themselves simply 

 leaves which have been modified for this purpose. In 

 some buds, for example the Horse Chestnut, you can 



FIG. 2. A spiny cactus, showing the rounded fleshy stem which is green, and 

 performs the food assimilation instead of the leaves. The true leaves are 

 modified into hard spines. 



find a gradual transition from the outermost brown hard 

 scales to the inner ones, which are soft and green. 



In some plants the leaves are all modified and 

 hard, and the stem does the work of assimilating. 

 For instance, in the Cactus the leaves are all reduced to 

 needle-like spines, but the stem is soft and fleshy and 

 ;;reen- coloured, and manufactures all the food. The 



