RHIZOMES AND ROOTS. 



243 



PLATE CVL 



FIG. 116. Powdered Jalap Root (x 240). 



a, a.', Starch in simple and compound grains. 



ca, Cambium cells. 



ccr, Crystal cells. 



cr, Crystals of calcium oxalate, 



f, Fibrous tracheids. 



gr, Droplets of resinous emulsion. 



I, Bast. 



pc, Cortical parenchyma. 



pi, Parenchyma of inner portion. 



s, s', Cork in surface view and profile, 



sc, Sclerenchymatous cells. 



v, vp, Vessels and debris of vessels. 



E 2 



