[*][*] Stems, at least the flowering ones, ascending or erect; flowers in corymbed or simple cymes; corolla-lobes obovate or obcordate.
[+] Calyx-teeth triangular-subulate; corolla-lobes rounded, entire; glabrous or nearly so.
3. P. ovàta, L. Stems ascending (½–2° high), often from a prostrate base; leaves oblong-lanceolate, or the upper ovate-lanceolate, and sometimes heart-shaped at the base, acute or pointed; flowers pink or rose-red, crowded, short-peduncled; calyx-teeth short and broad, acute. (P. Carolina, L.)—Open woods, in the mountain region from Penn. to Ala. June, July.
4. P. glabérrima, L. Stems slender, erect (1–3° high); leaves linear-lanceolate or rarely oblong-lanceolate, very smooth (except the rough and sometimes revolute margins), tapering gradually to a point (3–4´ long); cymes few-flowered and loosely corymbed; flowers peduncled (pink or whitish); calyx-teeth narrower and very sharp-pointed.—Prairies and open woods, N. Va. to Ohio and Minn., south to Fla. and Mo. July.
[+][+] Calyx-teeth long and slender; more or less hairy or glandular-pubescent.
[++] No runners or prostrate sterile shoots.
5. P. pilòsa, L. Stems slender, nearly erect (1–1½° high), usually hairy, as are the lanceolate or linear leaves (1–4´ long), which commonly taper to a sharp point; cymes at length open; calyx-teeth slender awl-shaped and awn-like, longer than the tube, loose or spreading; lobes of the pink-purple or rose-red (rarely white) corolla obovate, entire.—Dry or sandy woods, prairies, etc., N. J. to Minn., south to Fla. and Tex. May, June.
6. P. amœ̀na, Sims. Stems ascending (½–1½° high), mostly simple; leaves broadly linear, lanceolate or ovate-oblong, abruptly acute or blunt (½–1½´ long), on sterile shoots often ovate; cyme mostly compact and sessile, leafy-bracted; calyx-teeth awl-shaped or linear, sharp-pointed, but seldom awned, rather longer than the tube, straight; lobes of the corolla obovate and entire (or rarely notched), purple, pink, or sometimes white. (P. procumbens, Gray; not Lehm.)—Dry hills and barrens, Va. to Ky., south to Fla.
[++][++] Sterile shoots from the base creeping or decumbent; leaves rather broad.
7. P. réptans, Michx. Runners creeping, bearing roundish-obovate smoothish and thickish leaves; flowering stems (4–8´ high) and their oblong or ovate obtuse leaves (½´ long) pubescent, often clammy; cyme close, few-flowered; calyx-teeth linear-awl-shaped, about the length of the tube; lobes of the reddish-purple corolla round-obovate, mostly entire.—Damp woods, in the Alleghany region, Penn. to Ky. and Ga. May, June.