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..
[Calamintha Moench, Meth. 408. 1794.] Herbs, or low shrubs, with entire or sparingly dentate leaves, and rather large flowers variously clustered. Calyx tubular or oblong, mostly gibbous at the base, about 13-nerved, 2-lipped, naked or villous in the throat, the upper lip 3-toothed, the lower 2-cleft. Corolla usually expanded at the throat, the tube straight, mostly longer than the calyx, the limb 2-lipped; upper lip erect, entire or emarginate; lower lip spreading, 3-cleft. Stamens 4, all anther-bearing, didynamous, ascending under the upper lip of the corolla, somewhat con-nivent in pairs, the longer mostly exserted; anthers 2-celled, the sacs divergent or divaricate. Ovary deeply 4-parted; style glabrous, 2-cleft at the summit. Nutlets ovoid, smooth. [Greek, bed-foot, the flowers likened to a bed-castor.]
About 60 species, natives of the north temperate zone. Besides the following, 4 others occur in the southeastern United States and in California. The genus has been included in Satureia by authors. Type species: Clinopodium vulgare L.
* Flower-clusters dense, axillary and terminal, setaceous-bracted 1. C. vulgare.
** Flower-clusters loose, axillary, or forming terminal thyrses; bracts small. Plants pubescent; introduced species.
Clusters peduncled; calyx not gibbous; upper leaves very small; perennial.
2. C. Nepeta.
Clusters sessile; calyx very gibbous; plant leafy, annual.
Plants glabrous; native species.
Leaves linear or the lower spatulate, entire: corolla 4" long.
4. C. glabrum.
Leaves oblong or oblong-lanceolate, serrate; corolla 6"-7" long.
5. C. glabellum.
Clinopodium vulgare L. Sp. Pl. 587. 1753.
Melissa Clinopodium Benth. Lab. Gen. & Sp. 393. 1834.
Perennial by short creeping stolons, hirsute; stem slender, erect from an ascending base, usually branched, sometimes simple, 1°-2° high. Leaves ovate or ovate-lanceolate, petioled, obtuse or acutish, entire, undulate or crenate-dentate, rounded, truncate or sometimes narrowed at the base, thin, 1'-2 1/2' long; flowers in dense axillary and terminal capitate clusters about 1' in diameter; bracts setaceous, hirsute-ciliate, usually as long as the calyx-tube; calyx pubescent, somewhat gibbous, the setaceous teeth of its lower lip rather longer than the broader ones of the upper; corolla purple, pink, or white, little exceeding the calyx-teeth.
In woods and thickets, Newfoundland to North Carolina, Tennessee, Minnesota and Manitoba, in the Rocky Mountains to New Mexico and Arizona. Ascends to 4000 ft. in Virginia. Also in Europe and Asia. Stone-basil. Bed's-foot. Field- or horse-thyme. Dog-mint. June-Oct.
Melissa Nepeta L. Sp. Pl. 593. 1753. Cal. Nepeta Link & Hoffmansg. Fl. Port. 1: 14. 1809. Clinopodium Nepeta Kuntze, Rev. Gen. Pl. 515. 1891. Satureia Nepeta Scheele, Flora 26: 577. 1843.
Perennial by a woody root and short rootstocks, villous or pubescent; stem rather stout, at length much branched, the branches nearly straight, ascending. Leaves broadly ovate, petioled, obtuse or acute, crenulate with few low teeth, rounded or narrowed at the base, the lower 1/2'-1' long, the upper much smaller and bract-like; flowers few in the numerous loose peduncled axillary cymes, forming an almost naked elongated thyrsus; bracts very small, linear; calyx not gibbous, villous in the throat, about 1 1/2" long, the teeth of its lower lip twice as long as those of the upper; corolla light purple or almost white, about 4" long.
In fields and waste places, Maryland to South Carolina, Alabama, Indiana, Kentucky and Arkansas. Bermuda. Naturalized from Europe. Native also of Asia. June-Sept.