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..
Erect annual branching herbs, with broad or narrow leaves, and rather small yellow red purple or mottled verticillate-clustered flowers in the upper axils, or forming terminal dense or interrupted spikes. Calyx campanulate or tubular-campanulate, 5-10-nerved, 5-toothed, the teeth nearly equal, spinulose. Corolla-tube narrow, the throat expanded, the limb strongly 2-lipped; upper lip erect, concave, entire; lower lip spreading, 3-cleft, the middle lobe obcor-date or emarginate. Stamens 4, didynamous, ascending under the upper lip of the corolla, the anterior pair the longer; anthers 2-celled, the sacs transversely 2-valved, the inner valve ciliate, the outer smooth, larger. Ovary deeply 4-parted; style 2-cleft at the summit. Nutlets ovoid, slightly flattened, smooth. [Greek, weasel-like.]
About 6 species, natives of Europe and Asia. Type species: Galeopsis Tetrahit L.
Plant puberulent; leaves linear to ovate-lanceolate.
1. G. Ladanum.
Plant hispid; leaves ovate.
2. G. Tetrahit.
Galeopsis Ladanum L. Sp. Pl. 579. 1753.
Puberulent, sometimes glandular above; stem slender, erect, much branched, 6'-18' high, the branches ascending. Leaves linear, ovate-oblong, or ovate-lanceolate, mostly short-peti-oled, acute at both ends, dentate, or nearly entire, l'-2' long, 2"-8" wide; flower-clusters mainly axillary, distant; calyx-teeth subulate-lanceolate, shorter than or equalling the tube; corolla 6"-8" long, red or purple to white and variegated, twice the length of the calyx.
In waste places and on ballast, New Brunswick to Michigan, New Jersey and Indiana. Adventive or naturalized from Europe. Native also of Asia. Dog-nettle. July-Oct.
Galeopsis Tetrahit L. Sp. Pl. 579. 1753.
A coarse and rough-hairy herb, the stem rather stout, branched, 1°-3° high, swollen under the joints. Leaves ovate, membranous, slender-petioled, acuminate at the apex, rounded or narrowed at the base, coarsely dentate, 2'-5' long, 1/2'-2 1/2' wide; flower-clusters axillary, dense, or in a short leafy-bracted spike; calyx-teeth needle-pointed, bristly, as long as or longer than the tube; corolla 8"-12" long, pink or pale purple variegated with white, about twice the length of the calyx.
In waste places, Newfoundland to British Columbia and Alaska, south to North Carolina, West Virginia and Michigan. Naturalized from Europe. Native also of Asia. Bee-, dog- or blind-nettle. Stinging or flowering nettle. Nettle-, wild- or bastard-hemp. Simon's-weed. lune-Sept.