Herbs or rarely climbing shrubs with acrid sap; leaves usually alternate without stipules; flowers usually showy, blue, white, yellow, or scarlet; sepals 3—15, generally soon falling away, often petal-like; petals about the same number or occasionally wanting; stamens many; carpels many or rarely solitary.

A climbing or trailing vine with somewhat woody stems. Leaves trifoliate, the leaflets thin, on slender petioles, ovate, attenuate, acute, and entire, 2—3 inches long. Flowers purple, 1½—2 inches broad, on long peduncles, solitary in the axils of the leaves; sepals 4—6, oblong-lanceolate, acuminate, more than twice the length of the stamens; styles persistent, forming a plumose head of fruit.

In rocky woods and on shaded mountain sides up to 6000 feet elevation, throughout the Rockies, trailing over the ground, or festooning the shrubs or lower branches of the trees; flowering in early June.

Stem simple, sparingly hairy, 4—8 inches high. Basal leaves long-petioled, 3-parted, the broadly wedge-shaped divisions obtusely-lobed or crenate, those of the involucre nearly sessile, similarly lobed. Flower an inch or less in diameter, sepals, oblong, very obtuse, white, blue on the outside near the base; stamens numerous; head of fruit globose.

Common throughout the Rockies in moist ground and rich woods; flowering early in June.

Sparingly pubescent, with long whitish hairs, especially at the involucre, 4—6 inches high. Root leaves, slender-petioled, 3-parted, the divisions cut into linear, oblong obtuse lobes; leaves of the involucre similar on short petioles, their lobes slightly broader. Flowers usually solitary, half an inch or more broad on long peduncles; sepals 5, ovate or oval, obtuse, white, finely appressed-hairy and blue outside.

Throughout the region in alpine meadows and slopes near the snow, flowering in June and July as the snows disappear.

Stems 3—15 inches high, close, silky-hairy. Root leaves long-petioled, nearly semicircular in outline, 3-parted, the sessile divisions deeply lobed, with cleft, linear segments, involucral leaves similar, short petioled. Sepals 5—8, red, bluish or nearly pure white, half an inch or less long, soft, hairy outside, receptacle oblong, in fruit densely woolly.

The most abundant anemone through the Rockies in the low open valleys, and, occasionally on the slopes, presenting the greatest variety of colouring from deep rosy pink to pure white and occasionally blue; flowering in early June.

Villous, 6—18 inches high. Leaves much divided into narrow, linear, acute lobes, the basal on slender petioles, those of the involucre sessile and erect or ascending. Flowers bluish-purple, sometimes nearly white inside; sepals 5—7 ovate-oblong 1—1½ inches long, forming a cup; fruit a head of long silky achenes 2 inches or more in diameter.

This is one of the earliest and most beautiful of all the spring flowers, in the open meadows and mountain sides, blossoming through May and June according to the situation. Probably its most common local name, in the Rockies where it is very abundant, is that of crocus, to which flower it does bear a superficial resemblance, in size, shape, and colour, and in the habit of the flower appearing as soon as the snow has left the ground, and before the leaves.

Stem rather stout, silky-hairy, 6—18 inches high, simple. Leaves biternate, the lower on long petioles, the divisions deeply pinnatifid into deeply cut linear, acute lobes; those of the involucre similar but short-petioled. Flowers 1½—2 inches broad, peduncled, the peduncles much elongated in fruit; sepals spreading, 6—7, oval-obtuse, white, the outside usually blue at the base; fruit of long plumose tailed achenes in a globular fluffy head.

Frequent throughout the Rockies at an elevation of 6000 to 10,000 feet, blossoming on the edges of the snow banks as they recede, a conspicuous feature of many an alpine meadow during early June.

Smooth, pale green, and glaucous; stem purplish, erect, 6—18 inches tall. Leaves 3—4, ternate, long-petioled, leaflets firm, obovate, rounded at the apex, wedge-shaped or subcordate at the base, ¼—½ an inch long, 3—5-lobed, the lower surface prominently veined. Flowers diœcious, with 4 or 5 small, purplish-green sepals and large, linear, wedge-shaped anthers or slender styles; the achenes wedge-shaped and tapering into a short beak.

A frequent plant in the dry open valleys in the Rockies at the lower altitudes; flowering in June.

Stems slender, 1—3 feet high. Leaves 2—4, ternate, the lowest petioled; leaflets thin, ¼ to nearly an inch long, 3—9 lobed at the summit, sparingly glandular-hairy beneath. Flowers diœcious, nodding on very slender pedicels in an ample open panicle; calyx of 4—8 sepals which soon fall, filaments purplish and slender; anthers linear and pointed; achenes lanceolate or somewhat sickle-shaped, nearly half an inch long.

Frequent in rich woods and moist shady places at the lower altitudes throughout the Rockies; flowering in June, like the previous species striking for its leaves, resembling a robust maiden-hair fern, and the large loose heads of delicate tasselled flowers.

Aquatic herb with submerged stems, a foot long or more. Leaves petioled, 1—2 inches long, finely dissected. Flowers white with yellow centre, ½—¾ of an inch broad, blooming on the surface of the water on stout pedicels 1—2 inches or more long.

Frequent throughout the Rockies at the lower altitudes in shallow ponds and ditches; flowering in June and July.

Aquatic or creeping, hairy, at least on the younger parts. Leaves slender-petioled, ¼—1 inch, wide, palmately divided nearly to the base, into obtuse lobes. Flowers less than ½ an inch broad, bright yellow; petals 5; head of fruit globose, a little less than ¼ of an inch broad.

Frequent in shallow pools throughout the Rockies; flowering throughout the summer.

Stems creeping, rooting at the joints; flowering stems and peduncles ascending. Leaves linear-lanceolate or spatulate ½—2 inches long, entire, gradually narrowed into the petiole. Flowers nearly half an inch broad, solitary, on peduncles ¾—2 inches long; petals 4—7, much exceeding the calyx; stamens numerous; achenes flat.

On muddy shores of ponds and streams throughout the Rockies, flowering in midsummer, the creeping stems frequently interlaced and forming dense mats.

Erect 4—12 inches high, branching. Basal leaves petioled, broadly ovate or nearly orbicular, about ¾ of an inch broad, crenate or often lobed, those of the stem deeply and narrowly lobed, nearly sessile. Flowers about ⅓ of an inch in diameter, petals little surpassing the spreading sepals.

In moist shaded situations near Banff; flowering in June.

Stem branching, more or less hairy, 6—18 inches high, sparingly leafy. Leaves rounded in outline, mostly 5-parted, the segments cut into about 3-toothed lobes. Flowers of ¼ an inch or more broad, the light yellow petals surpassing the sepals; fruit in an obtusely ovoid head.

In wet springy places, ditches and the margins of pools, frequent through the Rockies at the lower altitudes; flowering in June and July.

Smooth, 3—12 inches high, 1—3-flowered. Leaves round in outline, those at the root all 3—5-parted and deeply cut; their obovate or wedge-shaped divisions mostly lobed or narrowly cut, stem-leaves similar with oblong to spatulate or lanceolate, often entire divisions. Flowers bright yellow; petals 5, a third of an inch or more long.

Frequent at the higher altitudes, blooming close to the melting snow, throughout the region; flowering in June and July.

Similar in habit to the previous species though usually larger, bright green and nearly smooth throughout. Leaves sparingly hairy on the margins, the basal broader and less divided. Flowers pale yellow, ¼ of an inch or more broad; petals little longer than the calyx.

Along streams and in moist grounds, an alpine species frequent throughout the Rockies; flowering in June and July.

Stems about 4 inches long, decumbent or ascending, smooth. Basal leaves on petioles 2 inches long, rounded, somewhat hairy when young, 3-lobed, lobes spreading and toothed, stem-leaves 1—3, nearly sessile, cleft into 3—7 linear lobes. Flowers about ½ an inch broad, sepals tinged with brown, half the length of the petals, broad, obovate, obtuse, slightly hairy; petals broadly obovate, bright yellow; achenes more or less hairy, with a straight style.

Throughout the Rockies in stony ground at the higher altitudes; flowering in July.

Stems rather stout, 6—12 inches high, slightly hairy. Root leaves on short petioles, rounded, crenate-toothed or 3-lobed, stem leaves sessile and cut into 3—6 oblong-lanceolate segments. Flowers ¼ of an inch or more broad, usually several together on short slender peduncles; petals obovate-oblong, light yellow; achenes small, hairy.

In open ground sparingly throughout the Rockies at the lower elevations; flowering in June.

Stem 3—6 inches high, smooth, slender, 1—3-flowered. Leaves ½ an inch or more long, sub-reniform or broadly fan-shaped with wedge-shaped base, deeply 3—5-cleft or parted, the radical into cuneate 3—5-cleft or incised divisions, those of the stem linear. Flowers bright yellow; petals round-obovate, ⅓—½ an inch long.

In moist ground on slopes, throughout the Rockies; flowering in June.

Stems hairy, 6—10 inches high, branching. Leaves few, basal, rounded in outline, ternately lobed, sometimes deeply so, on slender petioles; stem leaves sessile or nearly so, cut into narrowly linear or linear-lanceolate lobes. Flowers ¾ of an inch or more broad, petals spreading, bright yellow and shining on the upper surface; sepals not reflexed.

A showy low buttercup in the dry open valleys in the Rockies; flowering in June.

Stem stout, 1—2 feet high, branching with long rough hairs. Basal leaves long, hairy all over, 3-parted, the divisions again divided or cut into linear or lanceolate segments; petioles 3 or 4 inches long; stem-leaves similar but short petioled. Flowers few, large; sepals broadly ovate with silky hairs; petals broadly ovate, nearly half an inch long, bright yellow; head of achenes, globose; style long, slender, and much curved.

Frequent in the Rockies at the lower altitudes in more or less shaded grassy situations; flowering in June and July.

Stems creeping and rooting at the joints, 1—7-flowered. Leaves broadly ovate, coarsely crenate, clustered at the base and joints of the long slender runners. Flowers ¼ of an inch across; petals light yellow, longer than the sepals; fruit in oblong heads.

A common species throughout the Rockies in damp ground, frequently forming mats several feet across; flowering continuously throughout the summer.

Stems erect, 2—12 inches high, 1—2-flowered. Leaves roundish or oblong-cordate, longer than broad, irregularly crenate-toothed; sepals 6—8, lanceolate, ¾ of an inch long, white, strongly suffused with blue on the outside; stamens numerous; pistils 5—15.

In springy ground and wet alpine meadows throughout the region, often growing in such abundance as to make the meadows brilliant with the blue and white flowers, which appear soon after the snow has left the ground in June and July.

Stem erect, 6—12 inches high, more or less branching. Leaves palmately divided, the segments many cleft. Flowers solitary, 1—1½ inches broad, subtended by a whorl of leaves; sepals broadly obovate 5—6, pure white tinged on the back with greenish rose; petals 15—20, less than ¼ of an inch long, narrowly truncate, bright yellow, nearly concealed by the numerous stamens.

One of the most abundant and conspicuous of the spring flowers of the alpine meadows, and marshy borders of alpine streams and lakes, commencing to flower when but a few inches high on the edges of the melting snow in May and June.

One to two feet high, slender, sparingly branched. Leaves, the basal long-petioled, biternate, lobed and crenate, the stem leaves few, nearly sessile and lobed. Flowers ½ an inch or more long, nodding, sepals blue, petals creamy-white with a short blue spur not more than ¼ of an inch long; styles and stamens hardly exceeding the petals.

In open rocky situations, rather local, common in the region around Banff, flowering in May and June.

Stems smooth, 1—3 feet high, branched. Leaves ternate, leaflets round-cordate, 3-parted, the segments coarsely toothed, 2—3-cleft. Flowers yellow, an inch or more long, nodding; sepals reflexed, oblong-ovate, acute, longer than the spurs; petals spreading with a spur half an inch long; styles and stamens nearly equal, much exserted.

The commonest columbine throughout the region, growing in woods and on slopes up to 8000 feet, varying greatly in colour; flowering in June and July according to the elevation.

Stem 2—4 feet high, branching, sparingly pubescent with spreading hairs. Leaves, the lower triternately parted on long petioles, the upper sessile and ternate or reduced to simple bracts, leaflets broadly wedge-shaped, 3-cleft. Flowers scarlet, drooping, more than an inch long; sepals scarlet varying to orange, spreading or reflexed, an inch long, lanceolate, acute; petals yellow, more or less spreading, with a scarlet spur about the length of the sepals; styles and stamens exserted.

Throughout the Selkirks, in moist ground, on slopes and borders of rocky alpine streams, flowering during July and late June.

Stem tall, 2—5 feet high, leafy. Leaves mostly orbicular in outline, 5—7-parted, the upper into narrow-cleft, laciniate divisions, petioled. Flowers nodding, less than an inch long, dull purple, bluish or occasionally white, numerous in an elongated spike; sepals 5, blue, ⅓ of an inch long, not spreading, the upper one prolonged into a spur, half an inch long; petals white, nearly as long as the sepals.

Frequent in the region around Banff in open woods at the lower altitudes, flowering in July.

Sparingly leafy, 10—18 inches tall, from a tuberous rootstock. Leaves, the lowest round reniform, cut into irregular, oblong, obtuse lobes, the upper with linear, acute lobes. Flowers few in a simple panicle, sepals lanceolate, obtuse, ¾ of an inch or more long, spreading, brilliant blue, about as long as the short curved spur; petals exserted, white with purple veins.

Throughout the region in open ground and on grassy slopes; flowering in early June or later according to the altitude.

Stems erect, 2—3 feet high, smooth except the inflorescence. Leaves large, ternately compound, the basal leaf long-petioled, the divisions long petioled and pinnate, leaflets ovate, 1½—5 inches long, cut with sharp teeth. Raceme ovoid, 1—2 inches long; flowers small, white, with petal-like sepals; petals, 4—10 spatulate and minute; stamens numerous; berries in a spreading raceme, small, spherical, and purplish red.

Frequent in the rich woods throughout the region, at the lower altitudes; flowering in late May and early June.

Similar to the preceding species and often growing with it and difficult to distinguish from it when in flower: in fruit, however, they are quite distinct. In A. eburnea the berries are fully twice as large, nearly half an inch long and a quarter of an inch in diameter and pure waxy white.

In rich moist woods throughout the Rockies; flowering with the other species in May and early June; fruiting in late July.