4 P. Canadensis L. Villous-pubescent; st. sarmentous, procumbent and ascending; lfts. 5, obovate, silky beneath, cut-dentate towards the apex, entire and attenuate below; stip. hairy, often cleft; ped. axillary, solitary; bractlets longer than the sepals, and nearly as long as the petals. - Common in fields and thickets, U. S. and Can. Sts. more or less procumbent at base, from a few inches to a foot or more in length. Fls. yellow, on long pedicels. Cal. segm. lanceolate or linear. Apr. - Aug.
β. pumila T. & G. Very small and delicate, flowering in Apr. and May, everywhere; sts. a few inches long. (P. pumila Ph.)
simplex T. & G. Plant less hirsute; st. simple, erect or ascending at base; lfts. oval-cuneiform. Flowering Jn. to Aug. in richer soils. Sts. 8 to 14' high. Lfts. about 1' long, 2/3 as wide. (P. simplex Mx.)
5 P. argentea L. St. ascending, tomentous, branched above; lfts. oblong-cuneiform, with a few, large, incised teeth, smooth above, silvery canescent beneath, sessile; fls. in a cymous corymb; petals longer than the obtusish sep. - A pretty plant, on dry or rocky hills, Can. and N. States, remarkable for the silvery whiteness of the lower surface of the lvs. Sts. 6 to 10', long, at length with slender branches. Lfts. 5 to 9" by 1 to 2", with 2 or 3 slender, spreading tecth each side; upper ones linear, entire. Fls. small; cal. canescent; petals yellow. Jn.
6 P. recta Willi Erect, simple, pubescent; lfts 5 to 7, oblong or oblanceolate, coarsely serrate, with large, cleft stipules; fls. in a terminal, expanding cyme; petals obcordate, longer than the ovate, acute sep. - Cultivated and sparingly naturalized, N. Eng. to Ohio. St. 1 to 2f high. Fls. light yellow.
7 P. fruticosa L. St fruticous, very branching, hirsute, erect; lfts. 5 to 7, linear-oblong, all sessile, margin entire and revolute; petals large, much longer than the calyx. - A low, bushy shrub, N. States (Niagara Falls, Willoughby Lake, Vt. etc.) and Brit. Am. Sts. 1 to 2f high, with a reddish bark. Petioles shorter than the leaves Leaf about 1' by 2', acute, crowded, pubescent. Stip. nearly as long as the petioles. Fls. 1' diam., yellow, in terminal clusters. Jn., Aug. (P. floribunda, Ph.)
8 P. anserina L. Silver Weed. Goose Grass. St. slender, creeping, prostrate, rooting; lvs. interruptedly pinnate, lfts. many pairs, oblong, deeply serrate, canescent beneath; ped. solitary, 1-flowered, very long. - A fine species, on wet shores and meadows, N. Eng. to Arc. Am. Sts. subterraneous, sending out reddish stolons 1 to 2f long. Petioles mostly radical, 6 to 10' long. Lfts. 1 to 1 1/2' by 3 to 6", sessile, with several minute pairs interposed. Ted. as long as the lvs. Fls. yellow, 1' diam. Jn. - Sept
9 P. paradoxa Nutt. Decumbent at base, pubescent; lvs. pinnate, lfts. 7 to 0, obovate-oblong, incised, the upper ones confluent; stip. ovate; ped. solitary, recurved in fruit; petals obovate, about equaling the sep.; ach. 2-lobed, the lower portion a thick, starchy appendage. - River banks, Ohio to Greg., Isl. opposite St. Louis. St. 8 to 12' long. Lfts. 6' long, scarcely larger than the entire stipules. Jn., Jl. (P. supina Mx.)
10 P. Pennsylvanica L. Erect, canescently tomentous or soft-villous; lfts. 5 to 9, oblong, obtuse, pinnatifid or pectinate, upper ones crowded or confluent, larger; cyme fastigiate, at length expanding; petals emarginate, scarcely longer than the acute sepals. - N. Eng. (Pursh.); Can. N. W. to Siberia, (P. pectinata Fisch.)
11 P. arguta Ph. Erect, grayish, pubescent and villous radical lvs. on long petioles, 7 to 9-foliate, cauline few, 3 to 7-foliate, lfts. broadly ovate, cut-serrate, crowded; fls. in dense terminal cymes. - Along streams, etc., Can. and N. States, W. to the Rocky Mts. St. 2 to 3f high, stout, terete, striate, and with nearly the whole plant very hairy. Radical lvs. one foot or more long - lfts. 1 to 2' by 8 to 16", sessile, odd one petiolulate. Fls. about 8" diam.; pet. roundish, yellowish white, longer than the sepals; disk glandular, 5-lobed; anth. blackish, with a white border. May, Jn. (P. confertiflora Hitchcock. Boottia sylves-tria Bw.)
25. SIBBAL'DIA procumbens, L. "Mountains of Can. and Vt." (Pursh); but not since found within our limits.
26. SPIRAE'A, L. (Gr. a cord or wreath; the flowers are or may be used in garlands.) Calyx 5-cleft, persistent; petals 5, roundish; stamens 10 to 50, exserted; carpels distinct, 3 to 12, follicular,
1-celled, 1 to 2-valved, 1 to 10-seeded; styles terminal.- Unarmed shrubs or herbs. Branches and lvs. alternate. Fls. white or rose-color, never yellow.
§ Shrubs with lobed or pinnate, stipulate leaves........................................
Nos. 1, 2
§ Shrubs with simple leaves and no stipules...................................................
Nos. 3 - 6
§ Herbs perennial, with interruptedly pinnate leaves and perfect fls..........................
Nos. 7 - 9
§ Herbs perennial, with twice and thrice pinnate-leaves and dioecious fls......................
1 S. opulifolia L. Ninebark. Nearly glabrous; lvs. roundish, 3-lobed, petio-late, doubly serrate; corymbs pedunculate; carp. 3 to 5, inflated, and exceeding the cal. in fruit. - A beautiful shrub, 3 to of high, on the banks of streams, Can., Ind., Mo., S. to Ga., rare. Bark loose, outer layers deciduous. Lvs. 1 to 2 1/2' long, nearly as wide, sometimes cordate at base, with 3 obtuse lobes above; petioles 6 to 9" long. Corymbs resembling simple umbels, hemispherical, 2 1/2' diam. Fls. white, often tinged with purple. Follicles diverging, smooth, shining, purple, 2-seeded. Jn. †
β. ferruginea Nutt. Lvs. and branches brownish tomentous. - Ga., Fla.
2 S. sorbifolia L. Shrub stout, with straggling branches and rough bark; lvs. unequally pinnate, lfts. oblong-lanceolate, the terminal often larger, irregularly lobed, all acuminate, sessile and doubly serrate; fls. in thyreoid panicles, large, numerous, white. - In shrubberies. Height 4 to 6f. May. † Siberia.
3 S. tomentosa L. Hardhack. Ferruginous-tomentous; lvs. simple, ovate-lanceolate, smoothish above, unequally serrate; rac. short, dense, aggregated in a dense, slender, terminal panicle; carp. 5. - A small shrub, common in pastures and low grounds, Can. and U. S.,. particularly eastward. St. very hard, brittle, consequently troublesome to the scythe of the haymaker. Lvs. dark green above, rusty-white, with a dense tomentum beneath, crowded, and on short petioles. Fls. small, very numerous, with conspicuous stamens, light purple, forming a slender, pyramidal cluster of some beauty. The persistent fruit in winter furnishes food for the snow-bird. Jl. Aug.