BARKS. 



193 



FIG. 94. Powdered Cinchona Bark (Ledger) (x 240). 



a, Starch grains. 



or, Cells with sandy crystals of calcium oxalate. 



f I, f'l', Bast-fibres, entire and broken. 



I, Bast. 



lie, Debris of lichens. 



pc, Cortical parenchyma. 



rm, Medullary ray in long tudinal section. 



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



ph, Phelloderm. 



