Compilation
Melasma sessiliflorum

an erect herb, simple or loosely branched, glandular-hispid or nearly glabrous, annual, deep green in the living state, dusky when dry, 2–24 in. high or more, subparasitical; root saffron-yellow; stem or branches leafy, tetragonal; leaves triangular-ovate or lanceolate, obtuse, acute or acuminate at the apex, subtruncate or abruptly narrowed at the sessile or subsessile base, scabrid, rather thick, brittle, more or less coarsely toothed or denticulate or incise-dentate, sub-5-nerved, opposite, subopposite or alternate, mostly exceeding the internodes but sometimes shorter, 1/4–1 1/2 in. long, 1/6– 3/4 in. broad; flowers axillary or spicate, subsessile, usually numerous, about 1/2 in. long; spikes terminal; bracts sublinear or subulate, glabrous or ciliate, about 1/6– 1/5 in. long; calyx about 1/4 in. long, 5-cleft, campanulate, sparingly pilose outside, glabrous within; tube tetragonal, bibracteolate at the base; lobes lanceolate, ovate-acuminate or subdeltoid, acute, ciliate, about 1/6 in. long; corolla galeate-bilabiate, veined, bright golden-yellow or dull yellowish, red on the nerves, 5-cleft, glabrous; lobes obtuse, 3 lower larger than the others; stamens 4, didynamous or rarely 5 with the fifth shorter than the rest, glabrous or nearly so, the longer about equalling the corolla-tube; anther-cells usually apiculate at the lower end; ovary glabrous; style exceeding the stamens, somewhat thickened and bent above; stigma recurved, lingulate-oblong, somewhat flattened; capsules ovoid or subglobose, about 1/4 in. long; seeds numerous. null