BARKS. 



20] 



PLATE LXXXVIII. 



FIG. 98. Powdered Oak Bark (x 240). 



ccr, Cells containing rosette crystals. 



col, Collenchyma. 



cp, Prismatic crystals, free or enclosed in cells, abutting on the bast 



fibres. 



cr, Rosette crystals from the parenchyma of the cortex and bast. 

 fl, Fragments of bast fibres. 

 f I', The same, in transverse section. 



I, I', I'" Bast, in radial, transverse, and tangential section. 

 pc, Parenchyma of the cortex. 

 ph, PTaelloderm. 



rm, r'm', Medullary rays in radial and tangential section. 

 sc, Sclerenchymatous cells. 

 ten, Rows of crystal cells. 



