ORIGIN.--Belladonna is the leaves of a plant known as deadly nightshade. It grows wild in some parts of Great Britain, and is also cultivated to a great extent. The dried leaves of atropa belladonna yield, when assayed by the U. S. P. process, not less than 0.35 per cent of mydriatic alkaloids. Usually of a dull brownish-green color, the leaves much wrinkled and matted together, frequently with the flowering tops intermixed; odor distinctly narcotic, especially on moistening; taste somewhat bitter and acrid. Contains not less than 0.5 per cent atropine. The powdered leaves are characterized by few hairs and numerous small arrow-shaped crystals of calcium oxalate. DOSE.--Of the powdered leaves, horses and cattle, ¹⁄₂ to 1 oz.; sheep and pigs, ¹⁄₂ to 2 dr.; dogs, 1 to 5 grs. PREPARATIONS EXTRACTUM BELLADONNAE FOLIORUM--EXTRACT OF BELLADONNA LEAVES Made by percolation with dilute alcohol and evaporation to pilular consistence. Used in preparing the unguentum belladonnae. Contains 1.4 per cent of mydriatic alkaloids. DOSE.--Horses and cattle, 10 to 20 grs.; sheep and pigs, 2 to 4 grs.; dogs, ¹⁄₈ to ¹⁄₂ gr. TINCTURA BELLADONNAE FOLIORUM--TINCTURE OF BELLADONNA LEAVES Belladonna leaves 100, dilute alcohol to make 1,000, made by maceration and percolation. (Strength 10%.) DOSE.--Dogs, 3 to 30 ms. UNGUENTUM BELLADONNAE--BELLADONNA OINTMENT Extract of belladonna leaves, 10; dilute alcohol, 5; hydrous wool fat, 20; benzoinated lard, 63. BELLADONNAE RADIX--BELLADONNA ROOT DERIVATION.--The dried root of atropa belladonna yielding, when assayed by the U. S. P. process not less than 0.5 per cent of mydriatic alkaloids. CONSTITUENTS.--Same as leaves. Contains not less than 0.5 per cent atropine. PREPARATIONS FLUIDEXTRACTUM BELLADONNAE RADICIS--FLUIDEXTRACT OF BELLADONNA ROOT Made by maceration with alcohol and water and evaporation. One cc. of the extract = one gm. of belladonna root. Standardized so that 100 cc. of the fluidextract contain 0.5 gm. of mydriatic alkaloids. This is one of the most reliable preparations of belladonna. DOSE.--Horses, 1 to 2 dr.; cattle, 2 to 3 dr.; sheep and pigs, 10 to 15 ms.; dogs, 1 to 3 ms. LINIMENTUM BELLADONNAE--BELLADONNA LINIMENT Made by adding camphor, 50 parts to fluidextract of belladonna to make 1,000 parts (U. S. P.). ATROPINAE SULPHAS--SULPHATE OF ATROPHINE An alkaloid obtained from belladonna. As it occurs in commerce, it is always accompanied by small proportion of hyoscyamine extracted along with it, from which it cannot readily be separated. DERIVATION.--Atropine is obtained from a strong tincture of the root. PROPERTIES.--A white crystalline powder, very soluble in water and alcohol. DOSE.--Horses, ¹⁄₂ to 1¹⁄₂ grs.; cattle, 1 to 2 grs.; sheep and pigs, ¹⁄₂₀ to ¹⁄₁₂ gr.; dogs, ¹⁄₁₅₀ to ¹⁄₅₀ gr. The doses should be considerably reduced when used with morphine.