Herbs , perennial, from tubers or elongate, fascicled roots. Leaves basal and cauline, proximal leaves petiolate, distal leaves sessile or nearly so; cauline leaves alternate. Leaf blade palmately divided into 3-7 segments, ultimate segments narrowly elliptic or lanceolate to linear, margins incised and toothed. Inflorescences terminal, sometimes also axillary, 1-32(-more) racemes or panicles, to 28 cm; bracts leaflike, not forming involucre. Flowers bisexual, bilaterally symmetric; sepals not persistent in fruit; lower sepals (pendents) 2, plane, 6-20 mm; lateral sepals 2, round-reniform; upper sepal (hood) 1, saccate, arched, crescent-shaped or hemispheric to rounded-conic or tall and cylindric, usually beaked, 10-50 mm; petals 2, distinct, bearing near apex a capitate to coiled spur, concealed in hood, long-clawed; nectary present, on spur; stamens 25-50; filaments with base expanded; staminodes absent between stamens and pistils; pistils 3(-5), simple; ovules 10-20 per pistil; style present. Fruits follicles, aggregate, sessile, oblong, sides prominently transversely veined; beak terminal, straight, 2-3 mm. Seeds deltoid, usually with small, transverse, membranous lamellae. x =8.
Herbs perennial or pseudoannual, rarely annual, with taproots or 2 to several caudices. Stem erect or twining. Leaves simple or compound, cauline ones alternate, sometimes all basal, palmately divided, rarely undivided. Inflorescence usually racemose. Pedicel with 2 bracteoles. Flowers bisexual, zygomorphic. Sepals 5, petaloid, purple, blue, or yellow; lower sepals 2, narrowly lanceolate or oblong, small; lateral sepals 2, suborbicular; upper sepal falcate, navicular, galeate to cylindric. Petals 2, clawed; limb usually with lip and spur, secretory tissue usually at limb apex, rarely abaxial. Staminodes usually absent. Stamens numerous; anthers ellipsoid-globose. Carpels 3--5(--13); style short, persistent.
"Fls irregular; calyx corolloid, with unequal sep, the upper one (called the helmet) the largest, strongly arched or hooded, its tip prolonged forward and downward into a short beak; upper 2 pet concealed under the helmet, clawed, nectariferous at the tip; lower 3 pet vestigial or wanting; stamens numerous; pistils 3–5, the fr follicular; poisonous perennial herbs with broad, palmately cleft lvs and showy, mostly blue or white fls in a terminal raceme or panicle. 50+, Eurasia and N. Amer."
Brink, D. E. 1982. Tuberous Aconitum (Ranunculaceae) of the continental United States: Morphological variation, taxonomy and disjunction. Bull. Torrey Bot. Club 109: 13-23. Brink, D. E., J. A. Woods, and K. R. Stern. 1994. Bulbiferous Aconitum (Ranunculaceae) of the western United States. Sida 16: 9-15. Hardin, J. W. 1964. Variation in Aconitum of eastern United States. Brittonia 16: 80-94. Kadota, Y. 1987. A Revision of Aconitum subgenus Aconitum (Ranunculaceae) of East Asia. Utsunomiya. Munz, P. A. 1945. The cultivated aconites. Gentes Herb. 6: 462-505. Shteinberg, E. I. 1970. AconitumL. In: V. L. Komarov et al., eds. 1963+. Flora of the U.S.S.R. (Flora SSSR). Translated from Russian. 22+ vols. Jerusalem. Vol. 7, pp. 143-184.
|Monkshood, aconite, wolfsbane, aconit [according to Pliny, the name "aconite" is taken from the ancient Black Sea port Aconis]|