Aconitum Napellus, Linne. The dried tuberous root with not more than 5 p.c. of stems, nor 2 p.c. of other foreign organic matter.

Habitat. Europe, Asia, N. America, Himalaya, Alps, Pyrenees Mountains, 3,300-4,800 M. (11,000-16,000') elevation; cultivated in England, C. Europe.

Syn. Aconit., Aconite Root, Monkshood, Wolfsbane, Cuckoo's or Friar's Cap, Friar's Cowl, Wolfroot, Styrian Monkshood, Mousebane, Face-in-hood, Jackob's-chariot, Blue-rocket; Br. Aconiti Radix; Fr. Aconit Napel, Coqueluchon; Ger. Tubers Acniti, Eisenhutknollen, Sturmhut.

Ac-o-ni'tum. L.fr. Gr. cv, on, + rock -- i.e., it grows upon steep rocks in mountains; or fr. Fr. Acone, a town in Bithynia, where it grows plentifully.

Na-pel'lus. L.a little turnip; fr. Napus, a turnip -- i.e., medieval name from shape of roots, once used generically.

Plant

Perennial herb; stem .6-1.5 M (2-4degrees) high, round, smooth, leafy; leaves 5-10 Cm. (2-4') broad, palmately 3-7 divided, dark green above, lighter below, smooth, shining, petiolate, divisions wedge-shaped with 2-3 lobes extending midway; flowers Jul (third year), large beautiful, violet-blue, on stem's summit, racemes, sepals petaloid, nectariferous; fruit, 3-5 pod-like capsules. Root, produced at the end of a short rhizome, conical, fusiform, 4-10 Cm. 1-3/5-4') long, 1-3.5 Cm. (2/5 - 1 2/5') thick at crown; grayish-brown, smooth or longitudinally wrinkled, upper end with a bud, remains of bud-scales or a stem-scar, other portions with many root-scars or short rootlets; fracture short, horny, mealy; internally bark brownish, 1-2 Mm (1/25 - 1/12') thick, cambium zone 5-8-angled with a small fibro-vascular bundle in each angle; pith whitish, 2-7 Mm (1/12-1/4') broad; odor very slight; taste sweetish, acrid, soon developing tingling sensation, numbness. Powder grayish-brown -- numerous, spherical (plano-convex) starch grains, .003-.02 Mm (l/8326 -1/1250') broad, tracheae, stone cells tabular, irregular, fragments of cork (few) and parenchyma (many), stem bast-fibers (few, long). Solvent: alcohol. Dose, gr. 1-2 (.06-.13 Gm).

Adulterations

Allied aconite roots (A. Variegatum - much smaller, A. Fischeri - light gray, plump, smooth), defective roots, small horse-radish roots (collected only when leaves absent, as by these they may easily be distinguished), yellowish externally, taste exceedingly pungent, irritating; roots of European Masterwort (Imperato'ria (Peuced'anum)(Ostru'thium), which closely resemble aconite root, but are aromatic, pungent, with oil-cells arranged in several circles, easily visible in cross-sections.

(Aconitum Napellus; a, transverse section of tuber; b, fruit carpels; c, flowering branch; d, flower deprived of calyx, showing the only 2 peculiarly shaped petals, the 6 others almost aborted; e, tuber.)

Commercial

Plant grows wild, but under cultivation becomes slightly stronger, owing to which the Br. P. recognizes alone its root collected in autumn; all parts are very poisonous, a fact even known to the ancients, and was not introduced into medicine until 1762 (Baron Storck, Vienna); it is grown in gardens for ornamental flowers and when these have expanded, thereby insuring identity, the root should be collected. Imported mostly from Germany (England, France, Swwitzerland, India) in packages, bales, etc.

Constituents

Four alkaloids (one crystalline, three amorphous) .24-.62-1.15 p.c.: Aconitine (Crystalline), Picraconitine (benzaconine, isaconitine), C H O N, Aconine, Pseudaconitine (napelline), C H O N, aconitic acid, H C O H, starch, resin, fat, sugar, mannite.