416 XCIII. LABIATiE. Lycopus, 



2. M. vmiDis. (M. tennis. Michx. M. gracilis. Muhl.) 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. A well known plant, highly esteemed tor 

 its agreeable, aromatic properties. It grows in wet soils, rapidly spreading by 

 its creeping roots, with erect, branching, 4-angled stalks, 1 — 2f high. The 

 spikes are somewhat panicled, long, composed of distinct, axillary cymes, ap- 

 parently whorled, a little remote from each other. Peduncles smooth, round, 

 shining. Corollas pale purple. Styles much exserted. 



3. M. PIPERITA. Smith. Peppermint. 



Lvs. smooth, ovate-lanceolate, serrate, petiolate ; hracls lanceolate ; coa,. 

 quite smooth at base, punctate. — % This species, introduced from Europe, has 

 become naturalized in wet places, and cultivated in gardens. It has a more 

 penetrating taste and stronger smell than the other species, pungent to the 

 tongue followed by a sensation of coldness. The essence of peppermint is a 

 well known medicine, acting as a cordial, used in flatulency, nausea, &-c. It 

 has a purplish stem, 2 — 3f high, with scattered, deflexed hairs. Leaves sharply 

 serrate, dark green. Corolla purplish. July. 



4. M. ARVENsis. Corn Mint. Field Mint. 



St. ascending, much branched ; lvs. ovate, serrate, petiolate, acute, hirsute ; 

 verticils axillary, pedicels smooth; cat. hirsute. — Naturalized in Penn. Ohio, 

 &c., native in Europe. Stem stout, often erect, about If in height. Leaves 

 varying to oblong or ovate-lanceolate, sometimes nearly smooth, about twice 

 longer (1 — 2') than wide, several times longer than the petioles. Flowers 

 small, numerous, pale purple. Stamens exserted. The plant smells like de- 

 cayed cheese. July. 



5. ISANTHUS. DC. 



Gr. laos, equal, av^oi, the flowers being regular, a character very rare among the labiates. 



Calyx subcampanulate ; corolla 5-parted, tube straight and narrow, 

 segments of the border ovate and equal ; stamens subequal ; stigma 

 linear, recurved. 



I. ccERULEUs. Blue Gentian. 



Viscid, hairy ; lvs. oval-lanceolate, acute at both ends, 3-veined ; ped. 1 — 

 2-flowered. — Ij. A branching, leafy herb, in dry fields. Northern and Western 

 States ! with the aspect of the pennyroyal. Stem rounded, slender, 12 — 18' 

 high with branches and leaves opposite. Leaves an inch or less in length, and 

 a fourth as wdde, distinctly triple-veined. Flowers numerous, blue, with in- 

 cluded stamens. Calyx leaves lanceolate, longer than the tube. July. 



6. LYCOPUS. 



Gr. \vKos, a wolf, vovi, a foot ; a fanciful name. 



Calyx tubular, 4 — 5-cleft ; cor. subregular, 4-cleft, the tube as 

 long as the calyx, upper segment broadest, emarginate ; sta. 2, dis- 

 tant, diverging, simple ; sty. straight, as long as the stamens ; ach. 

 4, obliquely truncate at apex. — % 



1. L. siNUATUs. (L. Europaeus. Michx. L. Americanus. Muhl.) Wafer 

 Hiarhoimd. — Lvs. oblong-lanceolate, sinuate-dentate, lower ones incised ; 



teeth of the calyx acuminate-spinescent ; st. square, 1 — 2f high;_yZ5. small, white, 

 many in a whorl. — A perennial plant, widely diffused throughout the U. States, 

 growing in damp grounds. In habits and general appearance it resembles the 

 Mentha^, but is sufficiently distinguished by the number of stamens, form of 

 the flattened triquetrous achenia, and its being inodorous. Stem sharply 4- 

 angled, the sides concave, 1 — 2f high. Lower leaves deeply and pinnatifidly 

 toothed. Verticils dense. Calyx teeth longer than the achenia. It dyes a 

 permanent black. Aug. 



2. L. ViRGiNicus. Virginian, Water Hoarkound. Bugle-weed. 



Lvs. broad-lanceolate, serrate, tapering and entire at the base; calyx teeth 



