13. Potentilla Maculàta Pourret. Northern Cinquefoil

Fig. 2239

Potentilla maculata Pourr. Act. Toloss. 3: 326. 1788. Potentilla salisbrugensis Haenke in Jacq. Coll. 2: 68. 1788.

Rootstock prostrate, stems ascending, simple, pubescent, 3'-8' high. Stipules membranous; basal leaves slender-petioled, digitately 5-foliolate (rarely 3-foliolate); leaflets obovate, obtuse at the apex, narrowed or cuneate at the base, glabrous above, pubescent along the margins and on the veins beneath, green both sides, incisely dentate, with rounded or blunt teeth, 6"-9" long; flowers few, terminal, loosely cymose, yellow, 6"-9" broad; pedicels slender; petals obovate, obcordate, cuneate, yellow, orange-spotted at the base, longer than the ovate acutish calyx-lobes; stamens about 20; style filiform, terminal; achenes glabrous.

Labrador and Greenland to James Bay. Also in northern and alpine Europe and Asia. Summer. Confused with P. rubens (Crantz) Vill., in our first edition.

Potentilla Ranúnculus Lange, of Greenland and Labrador, differs in having the teeth of the leaflets lanceolate and acute.

14. Potentilla Nivea L. Snowy Cinquefoil

Fig. 2240

Potentilla nivea L. Sp. Pl. 499. 1753.

Stems 2'-6' high, woody at the base, ascending or erect, silky-villous, the flowering ones mostly simple. Stipules membranous, silky; leaves 3-foliolate (very rarely 5-foliolate), the lower petioled; leaflets obo-vate, oblong or oval, obtuse, incised-dentate or cre-nate, densely white-pubescent beneath, green and loosely villous above, 4"-8" long, the terminal one generally cuneate, the others narrowed or rounded at the base; flowers 1-5, terminal, pedicelled, yellow, 5"-9" broad; bractlets lanceolate to linear; sepals silky, lanceolate, acute, shorter than the broadly obovate emarginate petals, longer than the bractlets; stamens about 20; style filiform, terminal; achenes glabrous.

Quebec, Labrador, Greenland and throughout arctic America to Alaska and British Columbia, south in the Rocky Mountains to Utah and Colorado. Also in arctic and alpine Europe and Asia. Summer.

Potentilla Vahliàna Lehm., another high boreal species, differs in having oval or ovate bractlets and leaflets yellowish-villous beneath.

15. Potentilla Emarginàta Pursh. Arctic Cinquefoil

Fig. 2241

Potentilla emarginata Pursh, Fl. Am. Sept. 353. 1814.

Potentilla nana Willd.; Schlecht. Berl. Mag. 7: 296. 1815.

Stems villous-pubescent, tufted, ascending or erect, 1'-4' high. Stipules ovate or oblong, membranous, mostly obtuse, entire; leaves 3-foliolate, the basal slender-petioled; leaflets obovate, 2"-6" long, incised-dentate with acute teeth, of which the terminal one is generally the largest, generally villous on both sides, the terminal one narrowed or cuneate, the others sometimes broad at the base; flower solitary, rarely 2, yellow, 5"-7" broad; calyx-lobes ovate, obtuse, pilose, equalling the oblong bractlets, shorter than the obovate ob-cordate petals; stamens about 20; style filiform; achenes glabrous.

Labrador, Greenland and arctic America to Alaska. Also in eastern Siberia and Spitzbergen. Summer.