Vernonia
(named in honour of William Vernon, a botanical traveller in North America). Ironweed. Including Ascaricida and Webbia. ORD. Compositae. A vast genus (about 380 species) of stove, greenhouse, or hardy, annual or perennial herbs or shrubs, broadly distributed, chiefly in the tropics, but most copiously in the warmer parts of America. Flower-heads purple, reddish, bluish, or rarely white, terminal, solitary, cymose, or paniculate, homogamous; involucral bracts in many series, the inner longest; receptacle naked or pitted, sometimes shortly hairy; florets all equal, tubular, slender, narrowly five-cleft; achenes striated, ribbed, or angled, rarely terete; pappus of many hairs, often girt with a row of outer short hairs or flattened bristles. Leaves alternate (or in one Brazilian species opposite), entire or toothed, penniveined, sessile or petiolate. Few of the species are known to cultivation, the majority being mere weeds. Those described below thrive in rich, light soil, and may be readily increased by seeds, cuttings, or divisions, according to the nature of the plant.
V. acutifolia (acute-leaved). fl.-heads pale purple, sub-sessile at the sides of the branches; involucre hemispherical; florets forty. December. l. sessile, linear, acuminate, reticulate-nerved, slightly serrated, glabrous above, obscurely pilose beneath. Stem erect, terete. h. 4ft. South America. Greenhouse perennial. (B. M. 3062.) V. axilliflora (axillary-flowered). fl.-heads violet-purple, sessile, much shorter than the floral leaves; cymes long, scorpioid, terminal. September. l. shortly petiolate, oblong-elliptic, acute at both ends, nearly entire, scabrous and pilose above, villoustomentose beneath. Branches terete, villous. h. 1 1/2ft. Brazil. Stove shrub. (L. B. C. 1690.) V. Calvoana (Calvo's). fl.-heads white, 2in. broad, with a purple eye; involucral scales large and spreading, in many series; corymbs large, branching and spreading, bearing leafy, toothed bracts. January. l. sessile, oblong-lanceolate, acuminate, 8in. to 14in. long, toothed, much narrowed and unequally auricled at base. Stem stout, sulcate, branched, tomentose-pubescent. h. 8ft. to 12ft. Cameroons, 1861. A magnificent, stove shrub. (B. M. 5698.) V. centriflora (centre-flowered). A synonym of V. scorpioides. V. flexuosa (flexuous). fl.-heads purple or white; involucre campanulate, the bracts mucronate-acuminate; cymes scorpioid. September. l. sessile, oblong or linear-lanceolate, nearly entire, scabrous-pilose on both sides. Stem herbaceous, from a tuberous rhizome. h. 1 1/2ft. Brazil, 1823. Stove. (B. M. 2477; L. B. C. 1880.) V. noveboracensis (New York). fl.-heads purple; involucral scales tipped with a long, bristle or awl-shaped, spreading appendage, in some varieties merely pointed. August. l. lanceolate or oblong. h. 5ft. North America, 1710. Hardy perennial.
V. odoratissima (highly odorous). fl.-heads purple; involucral scales acuminate; cymes disposed in a panicle. October. l. shortly petiolate, rigid, obovate, cuneate at base, slightly toothed at apex, scabrid above, reticulated and hirsute-pubescent beneath. Stem terete, shrubby. h. 4ft. Caraccas, 1817. Stove.
V. pinifolia (Pine-leaved). fl.-heads bright purple; involucral scales mucronate, canescent; corymbs 3in. to 8in. across, mostly compound, of many heads, flat-topped. Summer. l. sessile, crowded, linear, acute, 1in. to 4in. long, half to four lines wide, becoming glabrous above, the margins revolute. Stems 1ft. to 2ft. high, mo-tly closely leafy throughout. South Africa, 1863. Greenhouse perennial. SYN. Webbia pinifolia (B. M. 5412). V. scorpioides (scorpioid-cymed). fl.-heads lilac-rose, sessile, contiguous; involucral scales hairy, the inner ones acuminate, the outer ovate; cymes scorpioid, recurved, leafless, approximate. Summer. l. petiolate, elliptic, acute, pubescent beneath. h. 1ft. Brazil and West Indies, 1874. Stove shrub. (R. H. 1874, 231.) SYN. V. centrijlora.
V. sericea (silky). fl.-heads purple or white, scssile, solitary or twin in the axils; involucre campanulate, the outer scales recurved, mucronate, the inner ones obtuse. December. l. very shortly petiolate, lanceolate, acuminate, sub-obtuse at base, sub-entire, nearly glabrous above, adpressedly pubescent beneath. Stem terete, striated, very slightly puberulous. h. 4ft. Brazil, 1823. Stove sub-shrub. (B. R. 522.)