534 THE STRUCTURE OF ECONOMIC PLANTS 



TABLE IV 



Relative Areas Occupied by the Different Tissues of the Cross Section 



OF A Mature Rhizome 



(After A rischwager) 



It will be noted from this table that the total transectional area 

 of the outer phloem exceeds that of the inner, and that the two 

 combined are approximately three times the area of the xylem, 



.1 .2 .3 .4 .5 mm. 



Fig. 183. Diagrammatic transection of mature rhizome showing proportional amount of 

 tissue in the principal zones. (After Artschwager, Jour. Agr. Kes.') 



