HYOSCYAMUS. 189 



show stomata. These are oval. A cross-section shows 

 the epidermis, with sHghtly thickened outer cutinized 

 wall, palisade tissues on the upper side only in a 

 single row filled with chlorophyll grains, the mesophyll 

 parenchyma with cells containing the crystal sand and 

 cross-sections of the fib ro- vascular bundles, which are 

 more prominent in the lower parts of the leaf. 



Powder. — This is brownish to dark green. The most 

 prominent features of a No. 60 powder are the epidermis 

 cells. Other elements are hairs, mesophyll parenchyma, 

 parenchyma of the fibro- vascular bundles, vessels, crystal 

 sand, and rarely crystals. 



The epidermal cells are characteristic, they are very 

 wavy and show very delicate wavy markings. The 

 stomata are slightly elongated and have from three to 

 four neighboring cells about them. The mesophyll 

 parenchyma varies. It is in some places isodiametric, 

 in others stellate. Large isodiametric cells imbedded in 

 the mesophyll contain fine crystal sand of calcium oxalate. 

 Larger calcium oxalate crystals of the rosette form 

 occasionally are formed, but these are inconspicuous in the 

 powder. 



The hairs are not diagnostic. They are few in number 

 and come from young leaves, on the petioles or under 

 sides of the chief veins in the older leaves. They are 

 usually simple multicellular hairs. Small glandular 

 hairs with short pedicles are also found. 



The vessels and fibres are few and not characteristic. 



Chemistry. — The chief constituents are atropine, some 

 hyoscyamine, and a trace of belladonnine. According 

 to some, the latter two are identical. Besides these there 

 is present asparagin and 14 to 15 per cent. ash. 



HYOSCYAMUS. 



Hyoscyamus is the leaf and seeds of Hyoscyamus niger. 

 Only the leaf will here be considered. Hyoscyamus is 



