POLYGONACEÆ

_Buckwheat Family_

Herbs and twining vines with alternate or sometimes opposite or

whorled leaves, jointed stems and usually sheathing united stipules;

flowers small, regular, perfect, monœcious, diœcious or polygamous;

petals none, calyx 2—6-parted, the segments more or less folded over

each other, sometimes petal-like; stamens 2—9 dilated at the base and

distinct or united into a ring; ovary superior, one-celled with a

solitary ovule.

Flowers not involucrate; stipules sheathing.

Leaves reniform, sepals 4. =Oxyria.=

Leaves not reniform; sepals 6.

Sepals unequal; stigmas tufted. =Rumex.=

Sepals equal; stigmas capitate. =Polygonum.=

Flowers involucrate, many; stipules wanting. =Eriogonum.=

[Sidenote: =Oxyria digyna= (L.) Hill. _Mountain Sorrel._]

Stems 2 inches to a foot high, scape-like and leafless, from a large

chaffy rootstock. Leaves basal on long petioles, reniform or orbicular

½—2 inches wide with a wavy margin, sometimes notched at the apex.

Racemes 2—3 inches or more long, of many small flowers on slender

pedicels; crimson or pinkish and showy in fruit.

Frequent at the higher altitudes throughout the region in moist grounds

and beside streams, flowering in June.

[Sidenote: =Rumex acetosa= _Sour._]

Stems a foot or more high, smooth. Leaves oblong, hastate or

ovate-sagittate, 1—4 inches long, acute, the basal few and long

petioled, stem leaves sessile, the acute auricles entire. Flowers,

diœcious, minute, crowded in a slender head 3—6 inches long,

yellowish-green tinged with red.

In moist open ground at the higher elevations, more or less frequent

throughout the Rockies, flowering in midsummer.

[Sidenote: =Rumex salicifiolus= Weinm. _Pale-leaved Dock._]

Smooth, pale green, erect, and spreading, 1—3 feet high. Leaves

lanceolate, acute or acuminate at both ends, petioled. Flowers

small greenish-white in erect or reflexed racemes, dense in fruit,

interrupted below; wings of the fruit triangular-ovate, with a large

ovoid tubercle.

Frequent throughout the Rockies at the lower altitudes; flowering in

summer.

[Sidenote: =Polygonum viviparum= L. _Alpine Bistort._]

Smooth, with a corm-like rootstock; stems solitary or clustered, 2—10

inches high. Basal leaves lanceolate or oblong. 1—8 inches long, rather

acute, cordate at the base on long petioles; stem leaves narrowly

lanceolate or linear, upper sessile with revolute margins. Flowers

in a dense terminal raceme several inches long; rose-coloured or

white; stamens exserted; small bulblets frequently developed among the

flowers, which later produce leaves and young plants.

Frequent in moist sandy soil and river banks throughout the Rockies,

flowering in June and July.

Several small weedy species of the genus are also found through the

region but are not sufficiently striking to be here described.

[Sidenote: =Eriogonum subalpinum= Greene. _Tall White Eriogonum._]

Stems depressed, much branched, prostrate and matted at the base.

Leaves oblong to ovate-spatulate, 1—2 inches long, on slender

petioles, smooth and green above, white-woolly beneath. Scape-like

peduncles, erect, 8—14 inches high, with a simple, large umbel of

8—12 rays subtended by a whorl of leaves. Flowers ⅛—¼ of an inch

high, cream-coloured or nearly pure white, and tinged with rosy pink

especially in age.

A striking plant growing in stony places and on rocky slopes,

throughout the Rockies, flowering in June and July.

[Sidenote: =Eriogonum ochroleucum= Small. _Yellowish-white Eriogonum._]

Tufted from a large rootstock. Leaves white and woolly throughout,

densely crowded on the very short stems, elliptic to obovate-spatulate,

half an inch or more long, narrowed at the base into slender,

frequently spirally-twisted petioles; scapes slender, several, six

inches or more high bearing a globular head of pale yellowish-white

flowers ³/₁₆ of an inch high.

On a moist rocky slope at an elevation of 4500 feet near Glacier,

abundant, the plant may occur elsewhere in the region but has not been

observed; flowers in June.

Alpine flora of the Canadian Rocky Mountains · 第 43 / 91 题