44 



B0TAN7. 



walled cells, which constitute a true meristem-tissue, to 

 which the name of Cambium * has been given (e, c, Figs; 26 

 and 21). Next to the cambium lie, in order, sieve-tissue 

 and soft tissue (parenchyma) ; these do not occupy separate 

 zones, but are more or less intermingled, forming a mass 



Fio. 28.— Fibro-vascular bundle of root ot Sweet Flag (Acorns), pp. plates of 

 traoheary tissue; g, g, pitted vessels; ph, sieve-tissue; s, bundle-sheatn. 



called the Soft Bast (y, y, y. Pig. 26, and^, Fig. 21). The 

 sieve-tissue includes sieve-tubes and cambiform or latticed 

 cells. In the extreme outer border of the bundle is a mass 

 of fibrous tissue {b, b). The layer of starch-bearing cells 



* Cambium, a low Latin word meaning a liquid which becomes glutinous. 

 The term was introduced when the real structure of the part to which it was 

 applied was not understood. 



