3. R. copallìna, L. (Dwarf S.) Branches and stalks downy; petioles wing-margined between the 9–21 oblong or ovate-lanceolate (often entire) leaflets, which are oblique or unequal at the base, smooth and shining above.—Rocky hills. July.—Shrub 1–7° high, with running roots.
[*][*] Flowers polygamous, in loose and slender axillary panicles; fruit globular, glabrous, whitish or dun-colored; the stone striate; leaves odd-pinnate or 3-foliolate, thin. (Poisonous.)—(§ Toxicodendron, DC.)
4. R. venenàta, DC. (Poison S. or Dogwood.) Smooth, or nearly so; leaflets 7–13, obovate-oblong, entire.—Swamps. June.—Shrub 6–18° high. The most poisonous species; also called Poison Elder.
5. R. Toxicodéndron, L. (Poison Ivy. Poison Oak.) Climbing by rootlets over rocks, etc., or ascending trees, or sometimes low and erect; leaflets 3, rhombic-ovate, mostly pointed, and rather downy beneath, variously notched, sinuate, or cut-lobed,—high-climbing plants (R. radìcans, L.) having usually more entire leaves.—Thickets, low grounds, etc. June.
[*][*][*] Flowers polygamo-diœcious, in small solitary or clustered spikes or heads which develop in spring before the leaves; leaves 3-foliolate; fruit as in first group. (Not poisonous).—(§ Lobadium, Torr. & Gray.)
6. R. Canadénsis, Marsh. Leaves soft-pubescent when young, becoming glabrate; leaflets rhombic-obovate or ovate, unequally cut-toothed, 1–3´ long, the terminal one cuneate at base and sometimes 3-cleft; flowers pale yellow. (R. aromatica, Ait.)—Dry rocky banks, W. Vt. to Minn., and southward.—A straggling bush, 3–7° high; the crushed leaves not unpleasantly scented.
Var. trilobàta, Gray. With smaller leaflets (½–1´ long), crenately few-lobed or incised toward the summit.—Long Pine, Neb., and common westward. Unpleasantly scented.
§ 2. CÒTINUS. Ovary becoming very gibbous in fruit, with the remains of the styles lateral; flowers in loose ample panicles, the pedicels elongating and becoming plumose; leaves simple, entire.
7. R. cotinoìdes, Nutt. Glabrous or nearly so; leaves thin, oval, 3–6´ long; flowers and fruit as in the cultivated Smoke-tree (R. Cotinus).—Mo. to Tenn., and southward.—A tree, 25–40° high.
Order 31. POLYGALÀCEÆ. (Milkwort Family.)
Plants with irregular hypogynous flowers, 4–8 diadelphous or monadelphous stamens, their 1-celled anthers opening at the top by a pore or chink, the fruit a 2-celled and 2-seeded pod.
1. POLÝGALA, Tourn. Milkwort.
Flower very irregular. Calyx persistent, of 5 sepals, of which 3 (the upper and the 2 lower) are small and often greenish, while the two lateral or inner (called wings) are much larger, and colored like the petals. Petals 3, hypogynous, connected with each other and with the stamen-tube, the middle (lower) one keel-shaped and often crested on the back. Stamens 6 or 8; their filaments united below into a split sheath, or into 2 sets, cohering more or less with the petals, free above; anthers 1-celled, often cup-shaped, opening by a hole or broad chink at the apex. Ovary 2-celled, with a single anatropous ovule pendulous in each cell; style prolonged and curved; stigma various. Fruit a small, loculicidal 2-seeded pod, usually rounded and notched at the apex, much flattened contrary to the very narrow partition. Seeds carunculate. Embryo large, straight, with flat and broad cotyledons, in scanty albumen.—Bitter plants (low herbs in temperate regions), with simple entire often dotted leaves, and no stipules; sometimes (as in the first two species) bearing cleistogamous flowers next the ground. (An old name composed of πολύς, much, and γάλα, milk, from a fancied property of its increasing this secretion.)
[*] Perennial or biennial; flowers purple or white; leaves alternate.
[+] Flowers showy, rose-purple, conspicuously crested; also bearing inconspicuous colorless cleistogamous flowers on subterranean branches.
1. P. paucifòlia, Willd. Perennial; flowering stems short (3–4´ high), from long slender prostrate or subterranean shoots, which also bear concealed fertile flowers; lower leaves small and scale-like, scattered, the upper ovate, petioled, crowded at the summit; flowers 1–3, large, peduncled; wings obovate, rather shorter than the fringe-crested keel; stamens 6; caruncle of 2 or 3 awl-shaped lobes longer than the seed.—Woods, in light soil, N. Eng. to Minn., Ill., and southward along the Alleghanies. May.—A delicate plant, with very handsome flowers, 9´´ long, rose-purple, or rarely pure white. Sometimes called Flowering Wintergreen, but more appropriately Fringed Polygala.
2. P. polýgama, Walt. Stems numerous from the biennial root, mostly simple, ascending, very leafy (6–9´ high); leaves oblanceolate or oblong; terminal raceme loosely many-flowered, the broadly obovate wings longer than the keel; stamens 8; radical flowers racemed on short subterranean runners; lobes of the caruncle 2, scale-like, shorter than the seed.—Dry sandy soil; common. July.
[+][+] Flowers white, in a solitary close spike; none cleistogamous.
3. P. Sénega, L. (Seneca Snakeroot.) Stems several from thick and hard knotty rootstocks, simple (6–12´ high); leaves lanceolate or oblong-lanceolate, with rough margins; wings round-obovate, concave; crest short; caruncle nearly as long as the seed.—Rocky soil, W. New Eng. to Minn., and southward. May, June.
Var. latifòlia, Torr. & Gray. Taller, sometimes branched; leaves ovate or ovate-lanceolate, 2–4´ long, tapering to each end.—Md. to Mich. and Ky.
4. P. álba, Nutt. Stems several from a hard rootstock, 1° high; leaves narrowly linear, 3–12´´ long, acute; wings oblong-obovate; crest small; lobes of the caruncle half the length of the appressed-silky seed.—Neb. and Kan. to Tex.
[*][*] Annuals, with all the leaves alternate; flowers in terminal spikes, heads or racemes, purple or rose-color, in summer; none subterranean.
[+] Keel conspicuously crested; claws of the true petals united into a long and slender cleft tube much surpassing the wings.
5. P. incarnàta, L. Glaucous; stem slender, sparingly branched; leaves minute and linear-awl-shaped; spike cylindrical; flowers flesh-color; caruncle longer than the narrow stalk of the hairy seed.—Dry soil, Penn. to Wisc., Iowa, Neb., and southward; rather rare.
[+][+] Keel minutely or inconspicuously crested; the true petals not longer but mostly shorter than the wings; seed pear-shaped.
6. P. sanguínea, L. Stem sparingly branched above, leafy to the top; leaves oblong-linear; heads globular, at length oblong, very dense (4–5´´ thick), bright red-purple (rarely paler or even white); pedicels scarcely any; wings broadly ovate, closely sessile, longer than the pod; the 2-parted caruncle almost equalling the seed.—Sandy and moist ground; common.
7. P. fastigiàta, Nutt. Stem slender, at length corymbosely branched; leaves narrowly linear, acute, 3–8´´ long; spikes short and dense (3´´ in diameter); the small rose-purple flowers on pedicels of about the length of the pod; wings obovate- or oval-oblong, narrowed at the base, scarcely exceeding the pod; bracts deciduous with the flowers or fruits, caruncle as long as and nearly enveloping the stalk-like base of the minutely hairy seed.—Pine barrens of N. J. and Del. to Ky., and southward.
8. P. Nuttàllii, Torr. & Gray. Resembles the last, but usually lower; spikes cylindrical, narrow; flowers duller or greenish purple, on very short pedicels; the awl-shaped scaly bracts persistent on the axis after the flowers or fruits fall; seed very hairy, the caruncle smaller.—Dry sandy soil, coast of Mass. to Mo., and southward.—Spike sometimes rather loose.
9.