P. Tormentilla: stems erect, or procumbent from a thick woody rootstock, forked, silky-hairy; lower leaves often shortly stalked, upper ones always sessile, consisting of three, rarely five, deeply-toothed leaflets; peduncles in the forks of the stem, or in the axils of the upper leaves, forming a loose, leafy, terminal cyme; flowers small, bright yellow, mostly with four petals; the first one, howrever, of each stem has occasionally five. - Heaths, moors, and pastures. Fl. June to August.
The Tormentilla reptans of authors is a more procumbent variety, occasionally creeping at the base, with rather larger flowers, more frequently furnished with five petals.
†† Petals usually Jive.
P. reptans: stems slender, prostrate, often rooting at the nodes; stipules ovate, mostly entire; leaves stalked, with five obovate, coarsely-toothed leaflets; flowers large, yellow, solitary, on long peduncles, axillary. - Cinquefoil. - Pastures, borders of woods, and hedges. Fl. June to August.
P. argentea: stems decumbent at the base, ascending; leaves long-stalked, of five wedge-shaped, deeply-toothed leaflets, the upper nearly sessile, all clothed beneath with close white down; flowers in a loosely-forked leafy corymb or panicle, rather small, yellow. - Gravelly pastures, wastes, and roadsides. Fl. June, July.
** Leaves pinnate, † Flowers yellow.
P. anserina: stem forming long creeping runners rooting at the nodes; leaves with numerous, oblong, deeply-toothed leaflets, shining silver-white with silky down beneath; peduncles long, solitary, bearing a rather large yellow flower. - Silverweed. - Roadsides and waste places. Fl. June and July.
†† Flowers purple.
P. Comarum: stems decumbent and rooting at the base, 1-1 1/2 feet high; stipules not distinct from the enlarged base of the leafstalk; leaflets 5-7, oblong, toothed, often hoary beneath; flowers few, in a loose, irregular corymb, clingy purple; inner segments of the calyx broad; petals shorter than the calyx; carpels numerous, small, on a somewhat enlarged, rather spongy receptacle. - Marsh Cinquefoil. - Marshes, and peat-bogs. Fl. June, July. [See also p. 53.]