The fresh leaves, with the branches to which they are attached, of Hyoscyamus niger, also the leaves separated from the branches and carefully dried, collected from plants of the second year's growth.

Characters. - Leaves sinuated, clammy, and hairy. The fresh herb has a strong, unpleasant odour, and a slightly acrid taste, which nearly disappear on drying. The fresh juice, dropped into the eye, dilates the pupil.

Composition. - A volatile alkaloid, hyoscyamine, soluble in water and spirit. It is decomposed, and its physiological action neutralised by caustic alkalis. It is isomeric with, but not identical with, atropine. Nitrate of potassium and other inorganic salts are present in the leaves.

Preparations.

B.P.

Dose.

Extractum Hyoscyami.................................

5-10 gr. or more.

Succus „ ...................................

30 min. to 1 fl. dr. or more.

Tinctura „ .................................

30 min. to 1 fl. dr.

U.S.P.

Abstractum Hyoscyami..................................

3-5 gr.

Extractum „ Alcoholicum..........

2 gr.

,, „ Fluidum.......................

5-10 min.

Tinctura „ ..................

1 fl. dr.