ACTIVITY OF THE CAMBIUM 



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FIG. 54. Activity of the cambium. A-D, diagrams of cambial 

 cell and its divisions (inner and outer tangential walls supposed 

 to be transparent, lateral radial walls opaque). A, single 

 cambial cell seen obliquely from within. B, first tangential 

 division (i). C, second tangential division (2); c, cambial cell; 

 x, xylem tissue mother cell ; p, phloem tissue mother cell. D, 

 diagram of tissue mother cell which has divided horizontally 

 to form a vertical file of short parenchyma cells. E, part of 

 cambium and tissues it has produced as seen in transverse section 

 under high power ; c, cambial cells ; v, xylem vessels ; t, tracheid ; 

 m.r., medullary ray cells ; s.t., young sieve tube ; p.p-, phloem 

 parenchyma ; w.p., wood parenchyma ; /, fibres. 



