752 LAMIACEAE 



Stem sparingly and coarsely pubescent or glabrous ; leaves glabrous or nearly so. 

 Leaves merely coarsely serrate. 



Leaves tapering at the base, rather thin. 3. L. lucidus. 



Leaves rounded at the base, thicker. 4. L. asper. 



Leaves sinuately pumatifid. .5. L. americaniis. 



1. L. communis Bickn. Rootstock tuberou.s-thickened at the base of the 

 stem; stem 1-8 dm. high, acutely angled; leaves 2.5-8 cm. long, lanceolate or 

 oblong-lanceolate, sharply serrate; calyx campanulate; corolla 2-3 mm. long; 

 lobes spreading. Wet places: Newf. — Va. — ^Neb. — Ore. — B.C. Plain — Suh- 

 mont. Au-S. 



2. L. velutinus Rydb. Stem 3-5 dm. high; leaf-blades lance-elliptic, 

 coarsely toothed, 4-10 cm. long, short-petioled ; cah-x campanulate, copiously 

 pubescent, 2.5 mm. long; lobes lanceolate, acuminate, the upper two recurved; 

 corolla 3.5 mm. long, glandular-punctate. Low ground and swamps: Colo. — 

 Tex.' — Miss. — Ark. Son. Au. 



3. L. lucidus Turcz. Stem stout, strict, 3-9 dm. high, sparingly pubescent 

 on the angles; leaves oblong-lanceolate, sessile or short-petioled, 5-15 cm. long, 

 sharply serrate; calyx-teeth subulate-lanceolate, nearly as long as the tube; 

 corolla little longer than the calyx. Wet soil, especially in thickets: Neb. — Kans. 

 — ^Ariz. — Calif. — B.C.; Asia. Plain — Submont. Jl-S. 



4. L. asper Greene. Stem 3-6 dm. high, obtusely angled; leaves firm, 

 narrowly lanceolate, acute, sessile, strongly serrate, 4-6 cm. long, very veiny, 

 rough on both sides; calyx-teeth ovate-lanceolate, acuminate. Wet places: 

 w Ont.— Neb.— B.C. Plain. Jl-Au. 



5. L. americanus Mulil. Stem sharply angled, puberulent or glabrous, 

 1-10 dm. high; leaves lanceolate in outline, petioled, acuminate, pinnatifid or 

 incised, 3-10 cm. long; cal>oc-teeth triangidar-subulate, cuspidate, rigid; corolla 

 little exceeding the calyx. L. sinuatus Ell. Swamps and wet meadows: Newf. 

 —Fla.— Calif.— B.C. Plain— Submont. Je-0. 



26. MENTHA (Tourn.) L. Mint, Spearmint, Peppermint. 



Aromatic caulescent perennial herbs, ^\-ith rootstocks. Leaves opposite, 

 punctate, toothed, usually petioled. Flowers perfect, in dense, axillary clusters. 

 Calyx campanulate, 10-ribbed, regular or nearly so, 5-lobed. Corolla funnel- 

 form or campanulate, nearly regular; lobes 4, the upper larger than the rest. 

 Stamens 4, anther-bearing, erect; anther-sacs 2, parallel. Nutlets smooth. 



Whorls of flowers forming terminal spikes. 1. M. spicata. 



Whorls of flowers all axillary. 



Stem and petioles densely pubescent with long viUous hairs; leaves decidedly pubes- 

 cent. 2. M. lanala. 

 Stem and petioles retrorsely strigose or crisp-hairy \sith short hairs, or glabrous 

 below; leaves sparingly puberulent or glabrous. 

 Corolla 5-6 mm. long, open-fvmnelform ; bracts lanceolate or linear-lanceolate, 

 usually e-xceeding the flower-clusters; leaves dark green, not strongly veined. 



3. i\/. occidcntalis. 

 CoroUa 4-5 mm. long, salver-shaped-funnelform; bracts linear or subulate, shorter 



than the flower-clu-sters. 

 Leaf-blades tliin, dark green, not strongly veined, tapering gradually into 

 slender petioles, which equal or exceed the flower-clusters. 



4. M. glabrior. 

 Leaf-blades thick, strongly veined, abruptly contracted into short petioles, 



which are much shorter than the flower-clusters. 

 Plant pale green, stout, 4-8 dm. high; calyx-teeth much longer than broad. 



5. M. Fcnardi. 

 Plant usually purpUsh, low, 2-4 dm. high; calyx-teeth scarcely longer than 



broad. 6. M. rubella. 



1. M. spicata L. Stem erect, 3-5 dm. high, glabrous; leaves lanceolate, 

 sessile or nearly so, sharply serrate, 3-7 cm. long; spikes 5-10 cm. long; bracts 

 subulate-lanceolate, ciliate; caly.x-teeth subulate; corolla glabrous. Spearmint. 

 Fields and waste places: N.S. — Fla. — Kans. — Minn.; Calif. — Utah — B.C.; nat. 

 from Eu. Plain — SubtJioni. Jl-S. 



2. M. lanata (Piper) Rydb. Stem 3-6 dm. high; leaves short-petioled, 

 lanceolate or ovate, serrate, 2-7 cm. long, more or less pilose above, villous 

 beneath; bracts subulate, about equalling the flowers; calyx 2.5-3 mm. long. 



