Arachis L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 191

74. Arachis L. 1

Annual. Leaves usually paripinnate with 2 pairs of leaflets; stipules linear, adnate to the petiole. Flowers sessile, in axillary racemes and with a long, tubular hypanthium. Calyx bilabiate, the upper lip (3-)4-toothed, the lower lip entire. Corolla yellow, adnate to the base of the stamen-tube; stamens monadelphous, the 2 adaxial stamens sterile. Legume cylindrical, torulose, indéhiscent, underground. Seeds 1-3.

After fertilization the base of the ovary elongates rapidly and buries the ovary in the ground. Subsequent development of the legume takes place underground.

Literature: B. W. Smith, Amer. Jour. Bot. 37: 802-815 (1950).