Castanea.
Castanea. N. F. IV. Chestnut Leaves.—"The dried leaves of Castanea dentata (Marshall) Borkhausen (Fam. Fagaceae), collected in September or October while still green, and without the presence of more than 5. per cent. of twigs or other foreign matter." N. F. It was official in the U. S. P., 1890. Of the few species included in the genus Castanea, two are natives of North America. Of these C. dentata has been considered by many botanists as identical with C. sativa Mill. (C. vesca Gaertn.), of Europe, and was described by Michaux as a variety of that species under the name of americana. Botanists at present, however, generally consider the two species as distinct. "Petioles stout, about 12 mm. in length; blades entire or slightly broken and usually folded or matted together; about 15 to 25 cm. in length and about 5 cm. in breadth, oblong-lanceolate, apex attenuate, acute at the base, coarsely and sharply serrate with ascending, attenuate teeth, nearly smooth, coriaceous in texture, the upper surface dark green, the lower light green; distinctly pinnately veined, the veins of the first order diverging at an angle of about 60 degrees, each terminating in one of the teeth. Odor slight; taste astringent. The powdered drug, when examined under the microscope, shows a few non-glandular hairs from 0.1 to 0.5 nun. in length, nearly smooth, thick-walled, distinctly yellow, occasionally in groups of three to eight and spreading from the base; numerous calcium oxalate crystals in rosette aggregates or in monoclinic prisms, from 0.01 to 0.04 mm. in diameter; parenchyma cells containing irregular yellowish-brown tannin masses which are colored blue with ammonio-ferric alum T.S. Castanea yields not more than 5 per cent. of ash.'' N. F. It is almost impossible to exhaust the leaves by percolation. Their odor is feeble and their taste slightly astringent. They yield their virtues freely to water, and probably less so to alcohol. John B. Turner found in chestnut leaves chlorophyll, tannin, gallic acid, gum, and albumen. (A. J. P., 1879, p. 542.) In addition to these constituents, L. J. Steltzer found potassium, calcium, magnesium, and iron carbonates, chlorides, and phosphates, and a trace of resin and fat. (A. J. P., 1880, p. 294.)
There is a popular superstition that chestnut leaves are of value in whooping cough, but the possession by them of any physiological or medicinal power is extremely doubtful. They may be administered in the form of a fluidextract which is official in the N. F.
Dose, one drachm (4 Gm.).
Castanea pumila. (L.) Mill., Chinquapin of the Southern United States, is a bush or small tree usually eight or ten feet in height, but in the Gulf States reaches sometimes thirty feet. The oblong, acute, mucronately serrated leaves are readily distinguished from those of the ordinary chestnut by being whitish and downy underneath. The tree produces a small, edible nut. The bark has been used as an astringent tonic. (For analysis, see A. J. P., 1899.)
