5. TRICHOSTEM'MA, L. Blue Curls. (Gr. hair, stamen ; for its long, hair-like filaments.) Calyx very oblique, veiny, unequally 5-toothed, lower lip of 2 short teeth, upper twice as long, of 3 teeth, all acute; corolla tube slender, short, limb obliquely 5-lobed; stamens 4,filaments very long, exserted and curved; anther cells divaricate.- Cymes loose, the central, that is, terminal fls. incurved, or re-supinate by the continued growth of the stem. Cor. blue.
1 T. dichotoma L. Lvs. oblong-lanceolate, attenuate at base, obtuse, entire pubescent, as well as the stem and branches.-Dry or rocky soils, Mass. to Ga., La., Ill. An interesting plant a foot high. St. obtusely 4-angled, hairy, bushy. Branches opposite and dichotomous. Lvs. slightly petiolate, 1' to 18" long, 4 to 7" wide. Fls. axillary and terminal, becoming inverted by the bending of the pedicel. Cor. purple. Stam. slender, of a delicate, purplish hue, gracefully bending from the lower lip of the corolla to the upper, forming an arch. Aug.
2 T. lineare Nutt. Lvs. linear, nearly smooth; st and branches puberulent.- Dry soils, N. Y. (at Salem) to Ga and La. Very slender, a foot high, branched above, or often its whole length. Lvs. 1' to 18" long, 2" rarely 3" wide. Cal. very veiny, the short triangular teeth setaceously acuminate. Fls. as in the other, about 4" long. Jl, Aug.
6. ISAN'THUS, Mx. False Pennyroyal. (Gr. equal, the flowers being regular; a character very rare among the Labiatae.) Calyx subcampanulate, equally 5-toothed, throat naked; corolla 5 parted, tube straight and narrow, segments of the border ovate and equal; stamens subequal, incurved, ascending, longer than the corolla.- Herb viscid pubescent, with lance-elliptic, entire lvs. acute at each end. Fls. axillary.
I. cœruleus Mx.-Branching, leafy, in dry fields, N. and W. States, with the aspect of Pennyroyal. St. rounded, slender, 12-18' high, with branches and lvs. opposite. Lvs. an inch or less in length, and a fourth as wide, distinctly tripli-veined. Fls. numerous, 1 or 2 in each axil, blue. Calyx leaves lanceolate, longer than the tube. Jl
7. MENTHA, L. Mint. (Mintha, the daughter of Cocytus, is fabled to have been changed into one of these plants.) Calyx equally 5-toothed; corolla nearly regular, tube scarcely exserted, border 4-cleft, the broadest segment emarginate; stamens 4, straight, distant; anther cells parallel ; filaments naked.- Strong scented herbs. Fls. in dense verticils.
§ Verticils apparoximating, forming a terminal, leafless spike...............................
§ Verticls remote, axillary. Calyx naked in the throat...........................................
1 M. viridis L. Spearmint. Lvs. subsessile, oblong-lanceolate, acute, incisely serrate; bracts setaceous, and, with the teeth of the calyx, somewhat hairy; spikes slender, interrupted, attenuate above.- Can. and U. S. Plant highly esteemed for its agreeable, aromatic properties. In wet soils, rapidly spreading by its creeping roots, with erect, branching, 4-angled stalks, 1-2f high. Spikes composed of distinct, axillary cymes, apparently whorled, a little remote from each other. Peduncles smooth, round, shining. Corollas pale purple. Jl., Aug. § Eur.
2 M. piperita Smith. Peppermint. Lvs. smooth, ovate, and lanceolate, serrate, petiolate; bracts lanceolate; cal. quite smooth at base, punctate; spikes oblong or cylindric, obtuse.-Wet places, and cultivated in gardeus. It has a more penetrating taste and stronger smell than the other species, pungent to the tongue, followed by a sensation of coldness. The plant has a purplish stem, 2 to 3f high, with scattered, deflexed hairs. Lvs. sharply serrate, dark-green. Spikes seldom more than 1' in length. Cor. purplish. Jl. § Eur.
3 M. arvensis L. Corn Mint. Field Mint. St. ascending, much branched, retrorsely hirsute; lvs. ovale, serrate, petiolate, acute, rounded or abrupt at base; verticils axillary; pedicels smooth; cal. hirsute.-Perm., Ohio, rare. St. stout, often erect, about If in height. Lvs. varying to oblong or ovate-lanceolate, sometimes nearly smooth, about twice longer (1 to 2') than wide, several times longer than the petioles. Fls. small, numerous, pale purple. The plant smells like decayed cheese. Jl. § Eur.
4 M. Canadensis L. Horsemint. Ascending, soft-pubescent with spreading hairs; lvs. petiolate, lanceolate, serrate, acute at each end; fls. in axillary cymes; stam. generally exserted.-Can. to Ky. and Penn. An herbaceous, grayish plant, 1 to 2f high, growing in muddy situations. St. square, usually branched and beset with spreading hairs. Lvs. serrate, on opposite, downy footstalks. Fls. apparently in whorls, pale purple. Calyx hairy. Aromatic like Pennyroyal but less so. Jn., Jl.
β. borealis. Plant nearly smooth. (M. borealis Mx.)
8. LYC'OPUS, L. Water Hoarhound. (Gr. a wolf, a foot; a fanciful name.) Calyx tubular, 4-5-cleft; cor. subregular, 4-cleft, the tube as long as the calyx, upper segment broadest, emargi-nate; sta. 2 distant, diverging, simple; Sty. straight, as long as the stamens ; ach. 4, obliquely truncate at apex.- Bog herbs, with the very small fls. in axillary, dense clusters.
1 L. Virginicus L. Bugle Weed. Lvs. broad-lanceolate, serrate, tapering and ontire at both ends; cal. teeth 4, obtuse, spineless, shorter than the achenia.-Can. and U. S., in wet soils. St. smooth, obtusely 4-angled, with the sides concave, 12 to 18' high, usually simple, bearing small whorls of minute purplish fls. Lvs. with remote, teeth-like serratures, petiolate or very slender at base. The whole plant often changes to purple. It often sends out long slender runners from the base. Jl, Aug.