LADIAT.E. (mint FAMILY.) 315 



5. P. muticum, Pcrs. Smooth or tomcntosc ; stem corymboscly branched; 

 leaves ovate or ovatc-lanccolate, acute, scrnxtc, rouiukil or sliglitly cordate at 

 the base, sessile or short-pi'tioled, the uppermost whitened ; cymes small, com- 

 pact, corymbose, minutely hoary-tomcntosc ; culyx-teetii short, triani^iilar-ovate, 

 obtuse. — Dry foil, Florida to Alississippi, and northward. Aug. and Sept. — • 

 Stem l°-2° high. Le.nves l'-2' long. 



^- H- 4- Cjmes capitate, in compact corymbose clusters: bracts shoHer than ihs 

 Jlowcrs : stem and rigid entire leaves smoothish. 



6. P. lanceolatum, Pursh. Stem branched ; leaves lanceolate or lincar- 

 lanccolatc, acute, i oundcd at the base ; cymes numerous, pubescent ; bracts 

 ovatc-lanccolate ; calyx-teeth short, triangular. — Dry soil in the upper districts. 

 Aug. and Sept. — Stem 2° high. Leaves l'-2' long. 



7. P. linifolium, Pursh. Stem bi-anched ; leaves very numerous, linear, 

 sessile; cymes smootliish ; bracts linear, acute ; calyx-teeth lanceolate-subulate, 

 rigid, acute. — Di'y soil, Florida to Mississippi, and northward. Aug. and Sept. 

 — Stem 1° high. 



8. P. nudum, Nutt. Smooth ; stem simple or corymbose at the summit, 

 straight ; leaves sessile, ovate-oblong, obtuse, rounded at the base ; cymes 

 smooth ; exterior bracts narrow-lanecolatc, the inner short, subulate ; calyx- 

 teeth short, triangular-lanceolate, and, like the corolla, pubescent. — Low pine 

 barrens, Dale County, Alabama, to the mountains of North Caroliua. Aug. 

 and Sept. — Stem 2° high. Leaves h' - 1' long. 



H- -1- ^- 4- Cjmes axilkirij and terminal, large, dcnse-Jlowercd : bracts ciliale. 



9. P. montanum, Michx. Stem slender, smooth, simple or branched; 

 leaves smooth, ovate-lanceolate, serrate, acute, tapering into a short petiole, the 

 lowest rounded at the base ; cymes globose, the upper ones closely sessile ; 

 bracts numerous, ciliatc ; the exterior ovate, very acute, as long as the flowers, 

 the inner ones linear ; calyx -teeth short, acute; ovary bearded. — Mountains of 

 North Carolina. July and Aug. — Stem 1° - 3° high. Leaves 2' -3' long. 



7. COLLINSONIA, L. Horse-Balm. 



Calyx obovatc, enlarged and dcflexed in fruit, 2-lippcd ; the upper lip flat- 

 tened, truncate, 3-toothcd, the lower 2-cleft. Corolla funnel-shaped, 2-lipped, 

 dilated at the throat ; the four upper lobes equal, the lowest larger, declining, 

 toothed or fimbriate. Stamens 2 or 4, long-cxserted, spreading : anther-cells 

 diverging. Nutlets smooth. — Strong-scented perennial herbs. Leaves large, 

 coarsely serrate, dotted beneath. Flowers yellowish, solitary, opposite, in 

 racemes or panicles. Petioles tumid at the base. 



* Fertile stamens 2. 



1. C. Canadensis, L. Nearly smooth; leaves ovate or o!)Iong-ovate, 

 acuminate, sharply seiTate, acute, rounded or cordate at the base, long-pctiolcd, 

 the uppermost smaller, sessile; panicle elongated; bracts minute, very acute; 

 flowering calyx very small, the upper lip much shorter than the lower, with 



