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late with tapering base and but slightly toothed margins; spikes few; flowers purple. In sandy fields, especially southward and as far north as Minnesota. The white vervain (V. urticaefolia) is a minutely pubescent perennial from three to six feet high; leaves oval; flowers white in slender spikes.

Mint Family (Labiatae).—A few shrubs and trees, but chiefly aromatic herbs, with square stems; opposite leaves

Fig.

137.

without stipules; flowers with cymose inflorescence; perfect, irregular, more or less two-lipped, the upper lip three-lobed, the lower two-lobed or entire; calyx fivetoothed or five-lobed; corolla four to fivelobed, commonly two-lipped, upper twolipped or entire, lower usually three-lobed; stamens borne on the corolla tube; ovary superior, deeply four-lobed or four-parted, in fruit forming four small seedlike nutlets or achenes surrounded by the persistent calyx; usually exalbuminous or some with albumen. A large order of about 3,000 species of very wide distribution.

Germander or Wood Sage (Teucrium canadense, L.).-A downy, erect perennial one to three feet high, with lanceolate to Hoary vervain ovate-lanceolate leaves, serrate, rounded at (Verbena the base, short petioled, and hoary understricta). neath; flowers in spikes; calyx fivetoothed; corolla five-lobed, upper lobes nearly equal, the lower lobe larger, all pale purple or rose color; stamens four, exserted. Common in fields, especially in low grounds from New England to Manitoba and Texas; abundant in Iowa, Minnesota and Missouri. Another species (T. occidentale) has viscid hairs on the calyx and flowers somewhat darker in color than the preceding. Common in low grounds in Iowa and Nebraska and is

found as far south as New Mexico and west to California. Horehound (Marrubium vulgare, L.).-A whitish, woolly, bitter, aromatic perennial with branched, ascending stems; leaves petioled, round-ovate, pointed, crenatetoothed; flowers in whorls; calyx with recurved, spiny teeth; corolla small, white, upper lip erect; stamens four, included in tube of corolla. Occasionally eastward. Common in Colorado and Utah and the Pacific coast. Very common in the foothills adjacent to the Salt Lake Basin. Catnip (Nepeta Cataria, L.).—A peren

nial, erect herb, one to three feet high; leaves ovate, cordate, coarsely serrate, petiolate, whitish, downy underneath; flowers in cymose clusters; corolla whitish, dotted with purple. Native to Europe; widely naturalized in the northern states.

Ground Ivy (Nepeta hederacea, (L.) Trevisan).-A creeping, trailing peren

nial, with leaves all alike; petioled, Fig. 138. Dead round, kidney-shaped, crenate, smooth, nettle (Lamium algreen on both sides; flowers light blue bum). Sometimes a very troublesome in axillary whorls of about six, appear- weed. (Ada Haying in early spring and summer. Na- den.) tive to Europe, widely naturalized in the northern states, especially in shady places.

Dead Nettle (Lamium amplexicaule, L.).-An annual herb with rounded, deeply toothed, crenate leaves; the upper leaves small, clasping; calyx tubular, five-toothed; flowers small; corolla purple, upper lip bearded, the lower spotted. Common in the eastern states to Missouri. The Lamium album troublesome in the East.

Motherwort (Leonurus cardiaca, L.).-Tall, perennial herb with erect stem, two to six feet high; leaves longpointed, the lower round and palmately lobed, the upper crenate at the base, three-cleft; flowers pale purple in

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 oblong

lanceolate, acute and sharply serrate; flowers whorled in interrupted, loose, leafless 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 Fig. 139. Black nightshade the lobes of the corolla and (Solanum nigrum). alternate with them, inserted on the tube, generally equal; style and stigma one; placentæ 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

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

(C. M. King.)

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 eleagnifolium, 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

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