314 LABIATA. (MINT FAMILY.) 
6. PYCNANTHEMUM, Michx. HORSE-MINT. 
4 E 
Calyx tubular, 13-nerved, naked in the 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: anthereells — 
parallel. Style 2-cleft at the apex. Nutlets smooth. — Perennial mostly piü- - 
bescent or hoary herbs, with erect branching stems. Floral leaves often white — 
tomentose. Cymes mostly terminal, bracted. Corolla small, white or purplish. 
— 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. : SS 
1. P. incanum, Michx. Stem densely pubescent and hoary ; leaves ovate 
or oblong-ovate, acute, sharply serrate, short-petioled, hoary-tomentose beneath ; n 
ealyx-teeth subulate, and, like the bracts, commonly bearded with weak hair. — 
(P. Loomisii, Nutt.) — Var. Turri. (P. Tullia, Benth.) Leaves smaller and — 
smoother; cymes larger and more expanded; calyx-teeth longer. — Var. At- 
BESCENS. (P. albescens, Gray.) Leaves ovate-lanceolate, obtuse, smooth above, 
hoary beneath; calyx-teeth triangular lanceolate, obtuse, not bearded. — Dry 
woods and fence-rows, Florida to Mississippi, and northward. Aug. and Sept. — 
Stem 2°- 4° high. Leaves 1'-2! long. Flowers white. des 
2. P. dubium, Gray. Stem villous-pubescent; leaves lanceolate, acute — 
at each end, smooth or nearly so, entire; cymes hoary, dense-flowered, short- 
peduncled ; calyx-teeth subulate, tipped, like the bracts, with a tuft of weak 
hairs; the 2 lower ones shorter. — Mountains of North Carolina. Aug. and 
Sept. — Stem 29-39 high. Leaves 2’- 3' long. ; 
i * ** Calyz-teeth nearly equal. ? J 
+ Calyx as long as the corolla; the teeth subulate and awn-pointed, like the rigid 
; bracts : cymes dense-flowered. 5 
3. P. aristatum, Michx. Tomentose and hoary, or sometimes hairy ; 
stem branched; leaves ovate or oblong, acute, sparingly serrate, rounded z - 
base, short-petioled, the uppermost somewhat whitened ; cymes mostly terminal; 
ovary bearded.— Var. HYSSOPIFOLIUM, Gray. Stem simple or corymbose 
above; leaves rigid, linear-oblong, obtuse, entire.— Low ground, Florida t0 
Mississippi, and northward. Aug. and Sept. — Stem 1}°-3° high. Leaves | 
I! - 2' long. rdi 
+ + Calyzx-teeth beardless and awnless : cymes capitate, mostly ‘terminal : bracts 
os shorter than the flowers: leaves subsessile. qst 
4. P. pilosum, Nutt. Softly pubescent or villous; branches short, erect; 
leaves lanceolate, entire, acute at each end, none of them whitened ; 
small, compact, corymbose ; calyx-teeth ovate-lanceolate, acute, and, like 
.— bracts, hoary-tomentose, or, in var. LEPTODON, Gray, subulate and villous. 
Upper districts of Georgia, and northward. Aug. and Sept.— Stem 2? high 
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