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close axillary whorls; corolla bearded. Native to Europe, widely naturalized in the northern states. Peppermint (Mentha piperita, L.).--Smooth, erect, perennial herb with creeping rootstocks from one to two feet high; leaves petioled, ovate, oblong to oblonglanceolate, acute and sharply serrate; flowers whorled in interrupted, loose, l e a fless spikes; purplish or whitish. Commonly escaped from cultivation and troublesome in the East. Nightshade Family (Solanaceae).- Herbs or vines, rarely shrubs; alternate leaves, sometimes opposite, in pairs and unequal (in a few of the tropical species, alternate without stipules); flowers regular or nearly so, borne in cymes; calyx inferior, fivelobed; stamens as many as the lobes of the corolla and alternate with them, inserted on the tube, generally equal; style and stigma one; placentae in the axils; ovules numerous; fruit a berry or capsule. A large family, chiefly tropical, consisting of 70 genera and 1,600 species, several of these being important medicinal plants and others valuable food plants. Common Nightshade or Stubbleberry (Solanum nigrum, L.).-Annual, low-branched and often spreading; glabrous or hairy, hairs simple, roughened on the angles; leaves ovate, petioled, flowers white, in small, umbel-like drooping lateral clusters; calyx spreading, the lobes obtuse, much shorter than the white corolla; berries glabrous, black, occasionally large. Found in northern

Fig. 139. Black nightshade (Solanum nigrum).

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Fig. 140. Horse nettle (Solanum carolinense). A most troublesome persistent weed with deep perennial root. (C. M. King.)

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part of the United States, also in Europe, in shady grounds and fields; a cosmopolitan weed. . Horse Nettle (Solanum carolinense, L.).-An herbaceous, deep-rooting perennial which propagates very freely by means of its deep underground roots, the running roots being frequently three feet long; stem from one to two feet tall, somewhat straggling and half shrubby at the base; rather rough and beset with numerous minute, star-shaped hairs and yellowish prickles; leaves two to four inches long, oblong or ovate, sinuatetoothed, lobed or deeply cut, and bearing spines; flowers borne in racemes which later become one-sided: calyx with slender lobes, corolla white or light blue, about oneinch in diameter, resembling that of the common potato; flowers followed by roundish berries one-half to threefourths inch in diameter. Somewhat widely scattered in central and eastern Iowa and at various points in Iowa; common in the South. Berries said to be poisonous, but not likely to cause trouble, since sheep, horses, and cattle refuse to eat them. Horseweed, Bull Nettle (Solanum cleagnifolium, Cav.). —A deep-rooted, spreading perennial from one to three feet high; stem silvery canescent, finely pubescent; leaves lanceolate, oblong or linear, petioled, entire or repand dentate; flowers in cymose clusters; peduncle stout and short; corolla gamopetalous, blue; calyx lobes lanceolate; berry yellow, smooth, globose. Common on the prairies of Kansas to Texas and New Mexico. Wright's Datura (Datura Metel, L.).-A spiny pubescent annual, pale in color, leaves obovate, entire; flowers large, showy, white or pale violet, sweet scented; corolla with a five-toothed border; capsule nodding, spiny. In waste places, escaped from gardens from Rhode Island to Florida. Purple Thorn Apple or Purple Stramonium (Datura Tatula, L.).--A glabrous annual from a few inches to five feet high; stem purplish; leaves thin, ovate, acute or acuminate; flowers consisting of a five-toothed calyx and a five-lobed funnel-form corolla, stamens included, filiform filaments inserted below the middle of the corolla tube: capsule globular, prickly, four-valved and two-celled. Abundant in fields and waste places from New England to Ontario to North Dakota, Nebraska, Texas and Florida; naturalized from tropical America. The Datura Stramonium of the same distribution has a green stem and a white corolla.

Fig. 14oa. Purple thorn apple (Datura Tatuia). Common around barns and roadsides. (Ada Hayden.)

Figwort Family (Scrophulariaceae).-Mainly herbs with a few shrubs and trees; leaves without stipules; flowers perfect, regular or irregular; calyx four to fivetoothed, cleft or divided ; corolla irregular, two-lipped or nearly regular; stamens two to five, didynamous or nearly equal, inserted on the corolla; pistil one, twocelled, many ovuled; fruit a capsule; seeds numerous, with a small embryo in copious albumen. About 2,500 species of wide distribution; few, however, of economic importance, although several are medicinal. Among the latter are foxglove (Digitalis purpurea) and mullein (Verbascum Thapsus).

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Great Mullein, Velvet Dock (Verbascum Thapsus, L.). —A tall, densely woolly annual from two to six feet high; leaves oblong, thick, covered with branched hairs, the basal leaves margined petioled; flowers in long, dense spikes; corolla rotate, yellow or rarely white; stamens unequal, the three upper shorter, woolly with short anthers; the two lower smooth with larger anthers. From Nova Scotia north across the continent, south to Missouri and Kansas and west to Utah. Moth Mullein (Verbascum Blattaria, L.).-Stem round, sparingly branched, biennial with smooth leaves, the lower petioled, oblong, ovate, lanceolate, laciniate, serrate, upper clasping; flowers in loose racemes, yellow or white with a tinge of purple; all stamens bearded with violet hairs; capsule nearly globose; seeds numerous. Common eastward, rare in the Mississippi Valley; abundant in the West in Salt Lake Basin. Toadflax, Butter and Eggs (Linaria vulgaris, Hill).-A smooth, erect, perennial herb, one to three feet high; leaves numerous, linear or nearly so, subalternate, pale; raceme dense, of Fig. 141. Toad- yellow flowers, corolla one inch or *... (*** * more long, with a spur at the base; garis.) upper lip erect, two-lobed, lower threelobed; calyx five-parted; stamens four, didynamous, not exserted; fruit a capsule, opening by one or more holes in the top; seeds small, numerous, winged. Fields and roadsides. Naturalized from Europe. Purple Foxglove (Digitalis purpurea, L.).-Biennial or annual pubescent herb with stout stem; lower leaves ovate or ovate-lanceolate, slender-petioled, upper leaves

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