LABIATE. (mint FAMILY.) 375 



sterile, included or wanting r anther cells parallel. Style 2-cleft at the apex. 

 Nutlets 3-augled, truncate at the apex, narrowed at the base. — Marsh or 

 aquatic mostly stoloniferous herbs. Leaves mostly toothed or pinnatifid. 

 Whorls dense, axillary. Flowers small, sessile, white. 



1. L. Virginicus, L. Stem smoothish ; leaves ovate-lanceolate, toothed- 

 serrate, acute or acuminate at each end ; calyx teeth 4, ovate, obtuse ; corolla 

 small, exserted; sterile stamens minute. — Ponds and ditches. Sept. — Stem 

 l°-2° high. Leaves l'-2' long. 



2. L. sinuatus, Ell. Stem 2° - 4^^ high, smooth, much branched ; leaves 

 pinuatifid-toothed, ovate-oblong, tapering at each end ; the upper ones nar- 

 rower ; calyx teeth 5, lanceolate-subulate, acute ; corolla twice as long as the 

 calyx ; sterile stamens minute or none. — Ponds and wet grounds. August - 

 Sept. 



3. L. rubellus, Mcench. Closely puljescent or tomentose; stem l°-2° 

 high, simple or branched, very leafy ; leaves ovate lanceolate, acuminate at 

 each end, coarsely serrate; whorls dense; calyx teeth subulate, pubescent, 

 nearly as long as the corolla ; seeds pitted. — Wet banks, mostly in the upper 

 districts. August -Sept. 



4. L. sessilifolius, Gray. Pubescent; stem simple or sparingly 

 branched ; leaves sessile, lanceolate or linear, toothed, serrate, or entire, resi- 

 nous-dotted ; calyx teeth subulate. — Ponds and ditches in the lower districts. 

 August -Oct. — Stem 2° -4° high. Leaves 2' -4' long. 



5. CUNILA, L. Dittany. 



Calyx tubular, 10-nerved, equally .5-toothed, hairy in the throat. Corolla 

 2-lipped ; the upper lip notched or entire, the lower 3-cleft. Stamens 2, dis- 

 tant, exserted : anther cells parallel. Style 2-cleft at the apex. Nutlets 

 smooth. — Perennial herbs. Flowers small, in corymbose or crowded whorls. 



1. C. Mariana, L. Smooth; stem slender, much branched ; leaves ovate, 

 serrate, acute, rounded or cordate at the base, subsessile ; cymes loose, axillary 

 and terminal, peduncled, mostly shorter than the leaves, corvmbose; calyx 

 teeth lanceolate, acute. — Dry soil along the mountains, Georgia, and north- 

 ward. July- Sept. — Stem 1° high. Leaves 1' long. Flowers purple. 



6. PYCNAWTHEMUM, Michx. Horse-mint. 



Calyx tubular, 13 nerved, naked in tlie throat, equally .5-toothed, or slightly 

 2-lipped. Corolla 2-lipped ; the upper lip notched or entire, the lower 3-cleft. 

 Stamens 4, nearly equal, straight, spreading, commonly exserted : anther cells 

 parallel. Style 2-cleft at the apex. Nutlets smooth. — Perennial mostly pu- 

 bescent or hoary herbs, with erect branching stems. Floral leaves often white, 

 tomentose. Cymes mostly terminal, bracted. Corolla small, white or pur- 

 plish. — Plants aromatic and pungent. 

 * Calyx more or less 2-lipped, the subulate teeth often bearded with weak jointed 



hairs: cymes mostly terminal, widely spreading in fruit: bracts longer than 



the flowers : leaves pubescent, the uppermost whitened. 

 1. P. incanum, Michx. Stem densely pubescent and hoary; leaves 

 ovate or oblong-ovate, acute, sharply serrate, short -petioled, hoary-tomentose 



