WOOD AND BARK. 



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innermost and darker part (x) is made up of tissues 

 which become hard in shrubs and trees, and form the 

 xylem* or wood. The outer and lighter parts (cb) are 

 made up of tissues which are called phloem^ or bast. 



The wood and the bast do not continue to grow, 

 but between them is a set of living and growing cells, 

 called the cambium. These cambium cells form new 



* From the Greek " xulon" wood. 



t From the Greek " phloios" the inner bark, bast. 



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