This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Herbs or shrubs, often stellate-pubescent, sometimes climbing. Flowers cymose, umbel-liform, paniculate, or racemose, white, blue, purple, or yellow. Calyx campanulate or rotate, mostly 5-toothed or 5-cleft. Corolla rotate, the limb plaited, 5-angled or 5-lobed, the tube very short. Stamens inserted on the throat of the corolla; filaments short; anthers linear or oblong, acute or acuminate, connate or connivent into a cone, the cells dehiscent by a terminal pore, or sometimes by a short introrse terminal slit, or sometimes also longitudinally. Ovary usually 2-celled; stigma small. Berry mostly globose, the calyx either persistent at its base or enclosing it. [Name, according to Wettstein, from solamen, quieting.]
About 1000 species, of wide geographic distribution, most abundant in tropical America. Besides the following, some 20 others occur in the southern and western United States. Type species: Solanum nigrum L.
1. S. nigrum.
Leaves deeply pinnatifid; ripe berries green.
2. S. triflorum.
Plant silvery stellate-canescent; flowers violet.
4. S. elaeagnifohum.
** Stellate-pubescent and prickly herbs. Berry not enclosed by the calyx; perennials.
Hirsute: leaves'ovate or oblong, sinuate or pinnatifid.
3. S. carolinense.
Densely silvery-canescent; leaves linear or oblong, repand or entire.
4. S. elaeagnifolium.
Pubescent; leaves ovate, 5-7-lobed.
5. S. Torreyi.
Plant densely stellate-pubescent: corolla yellow.
6. S. rostratum.
Plant glandular-pubescent, with few stellate hairs; corolla violet.
7. S. citrutlifolium.
Anthers all equal.
8. S. sisymbnfohum.
*** Climbing vine, not prickly; leaves hastate or 3-lobed.
9. S. Dulcamara.
Solanum nigrum L. Sp. Pl. 186. 1753.
Annual, glabrous, or somewhat pubescent with simple hairs, green; stem erect, branched, 1°-2 1/2° high. Leaves ovate, petioled, more or less inequilateral, 1-3' long, entire, undulate, or dentate, thin, acute, acuminate or acutish at the apex, narrowed or rounded at the base; peduncles lateral, umbel-lately 3-10-flowered, 1/2'-1 1/2' long; pedicels 3"-7" long; flowers white, 4"-5" broad; calyx-lobes oblong, obtuse, spreading, much shorter than the corolla, persistent at the base of the berry; filaments somewhat pubescent; anthers obtuse; berries black when ripe, smooth and glabrous, globose, 4"-s" in diameter, on nodding peduncles.
In waste places, commonly in cultivated soil, Nova Scotia to the Northwest Territory, south to Florida and Texas. Widely distributed in nearly all countries as a weed, and includes numerous races, differing principally in leaf-form and pubescence. Petty-morel. Duscle. Hound's-berry. July-Oct.
Solanum villosum (L.) Mill., with coarsely dentate leaves, the pubescence villous and somewhat viscid, has been found in ballast about the seaports.