506 



POWDERED DRUGS 



are likely to have a stalk composed of several superimposed cells. The 

 unicellular glands are rounded in form and are borne on stalks of several 

 cells, pg, Fig. 279. 



It should be stated that each drug has its own peculiar microscopical 

 elements. Some of these, it is easy to see, are of special value in the 

 identification of drug powders. 



FIG.' 279. Powdered Belladonna Leaves. (X 210.) c, cr. Cells with sandy crystals, cq, 

 Collenchymatous cells from cortical tissues of midrib, ei. Epidermis of under surface, en. Epi- 

 dermis over the veins, with striated cuticle. e.<t. Epidermis of the upper surface, with striated cuticle 

 and occasional stomata. /, Bast, me. Branching cells of spongy parenchyma, nv, Fragment of 

 small vein, pa, Palisade cells, surface view, p'a'. Palisade cells, in longitudinal section, pg, Glan- 

 dular hairs, long and short, with unicellular and pluricellular glands, st, Stomata, surrounded by 

 three or four cells, one of which is smaller than the others. //, Cortical tissues of the midrib, tr, v, 

 Tracheids'and vessels. (After Greenish and Collin.) 



