128 PLANT ORGANS OR PARTS OF PLANTS. 



Fig. 28. — Podophyllum Rhizome. 

 Upper figure, section of cortex; lower, of fibro- vascular bundle: 

 Ck, Corky layer; Cort, cortical parenchyma, with starch grains and 

 crystals, represented in single instances only; BF, bast fibres; ST, 

 sieve tubes; C, cambium; T, tracheid; WP, woody parenchyma cells; 

 V, vessels: SV, spiral vessel; WF, wood fibres; Par, parenchyma of 

 center (pith). i 



