Indian Azadirach (Neem Bark; Margosa Bark)

The dried stem-bark of Melia Azadirachta, Linne (N.O. Meliaceoe), a tree indigenous to India and Malay Archipelago. Channelled, tough, fibrous pieces up to 10 mm. thick. Externally brownish grey, rough and scaly or fissured; internally yellowish, conspicuously laminated and coarsely fibrous. Transverse section minutely chequered, pale narrow medullary rays and tangential bands of parenchyma alternating with darker groups of bast fibres. Under the microscope the latter are seen to be surrounded by lignified parenchyma. Contains a bitter, amorphous resin, a crystalline, bitter alkaloid (margosine), margosia acid, a crystalline substance and tannin. Used in India as a bitter tonic.

Note

The seeds yield margosa oil; the pulp of the fruit is used in India as an ingredient in curries.

Piscidia (Jamaica Dogwood). The root-bark of Piscidia Erythrina, Linne (N.O. Leguminosoe), a West Indian and South American shrub. Quills or curved pieces, 5 to 15 cm. long, 4 to 6 mm. thick. Externally orange brown to dark reddish brown, with thin longitudinal and transverse ridges, somewhat fissured. Inner surface brown, smooth or fibrous. Fracture tough, fibrous, showing greenish patches. Odour characteristic, taste bitter, acrid. Contains crystalline, piscidin, bitter glucoside, resin. Used as a sedative in neuraglia, irritant coughs; also for dysmenorrhoea and nervous debility. Used in Jamaica as a fish poison.

Calotropis (Mudar Bark)

The dried root-bark of Calotropis procera, Robert Brown (N.O. Asclepiadeoe), a tree indigenous to India and Ceylon. Short quilled pieces, 2 to 5 mm. thick, 2 to 4 cm. wide, occasionally with rootlets attached. Cork soft, pale buff, longitudinally furrowed, wrinkled; inner surface pale yellow, granular. Section exhibits a thick buff coloured cork and white inner portion. Cortex and bast contain abundant laticiferous vessels. Starch very characteristic; simple grains 3 to 10 long, with distinct hilum and conspicuous striations; compound grains with two component grains. Taste bitter and acrid. Contains a yellow bitter resin; black acid resin; crystalline colourless madaralbin; yellow madarfluavil. Used as a diaphoretic and expectorant; as a substitute for ipecacuanha.

Condurango

The bark of Gonolobus Condurango, Triana (N.O. Asclepiadeoe), a climbing plant indigenous to Ecuador. Quilled or curved pieces, 5 to 10 cm. long, 05 to 2 cm. wide and 2 to 6 mm. thick. Cork thin, greyish brown, often warty, sometimes scaly; inner surface paler, coarsely striated. Section pale, exhibiting scattered groups of sclerenchymatous cells. Almost odourless; taste bitter, rather acrid. Contains numerous laticiferous vessels, groups of sclerenchymatous cells and bast fibres, and abundant cluster-crystals of calcium oxalate. Constituents imperfectly known; one or more toxic glucosides and a toxic resin. Condurangin is the name applied to a mixture of glucosides; soluble in cold water, precipitated by boiling, re-dissolved on cooling. Used as a cure for cancer, but is useless.

Elm Bark

The inner branch and trunk bark of Ulmus campestris, Linne (N.O. Urticaceoe). Flattened pieces, 10 to 12 cm. long, 3 to 5 cm. wide and about 5 mm. thick. Outer surface yellowish or brownish, often with dark brown patches of the outer portion; fracture short, somewhat fibrous; section shows numerous dark, usually oblique, medullary rays and tangentially elongated, whitish groups of bast fibres. Inodorous; tastes lightly astringent, mucilaginous. Contains tannin, mucilage and starch. Formerly used as an astringent.

Larch Bark

The bark of Larix europoea, de Candolle (N.O. Coniferoe), central and southern Europe. Flat, curved, or channelled pieces; seldom in quills. Outer portion dark brownish red, often several centimetres thick, laminated; tissue between the laminae often rose pink; inner portion nearly white. Odour terebinthinate; taste astringent and terebinthinate. Contains tannin and crystalline larixin, C10H10O5, allied to pyrogallol. Formerly used as an astringent, stimulant and expectorant; now seldom employed.