1 34 POLYGONACEAE. 



acute, and rather prominent teeth, often dark brown; flowers white, rose-color 

 or yellowish, % line long. 



Dry interior plains, valleys and low hills. 



11. E. virgatum Benth. Tomentose throughout, stem slender, erect, simple, 

 or the few branches strict, 1 to 2 ft. high; leaves rosulate at the base, oblanceo- 

 late, an inch or two long, on slender petioles, the margin usually undulate; 

 involucres rather remote, tomentose, cylindric, 2 lines long; bracts lanceolate, 

 shorter than the involucres; flowers 1 line long, buff or sulphur-yellow. 



Stream beds at low altitudes: Coast Eanges and Sierra Nevada. 



12. E. dasyanthemum T. & G. Plants clothed with a thin coat of tomen- 

 tum which is soon deciduous, 1 to 2 ft. high, more or less umbellately branch 

 ing from or near the base, and often very bushy in habit; leaves roundish, 

 plane, tomentose below, less so above, % to iy 2 in. long, abruptly contracted 

 to a slender petiole as long or half as long; involucres rather remote, cylindric, 



2 lines long, tomentose between the callous ribs; flowers few, scarcely exserted, 

 white or rose-color, densely villous on the outside. 



Vaca Mts. to Clear Lake. Var. jepsonii Greene in herb. Lower branches in 

 whorls of 3 to 5; lower leaves 2 in. long; panicle ample; flowers deep red. 

 — Vaca Mts. 



13. E. angulosum Benth. Gray tomentose or nearly green, 3 to 14 in. 

 high, diffusely branching from near the base, and repeatedly dichotomous, the 

 plants frequently broader than high; branches 4 to 6-angled; radical leaves 

 roundish to broadly oblong or lanceolate, commonly undulate, !/> to 1 in. long, 

 on rather short petioles; upper leaves oblong to lanceolate or oblanceolate, ses- 

 sile or nearly so; involucres on filiform pedicels 3 to 8 lines long, mostly in the 

 forks or terminal, hemispherical, 1 to 2 lines broad, many-flowered, glabrous 

 or minutely glandular, bractlets mostly firm and dilated; calyx-segments pink 

 with a red-purple midvein running nearly to the apex, % line long, nearly 

 glabrous; outer segments ovate, concave, the inner oblong-lanceolate. 



South Coast Eanges and San Joaquin Valley to Southern California, common. 



Oxyria digyna Campt. Mountain Sorrel. Alpine perennial herb; leaves 

 round-reniform, long-petioled, mostly radical; sepals 4; achene surrounded 

 by a broad wing and thus orbicular in outline. — Sierra Nevada, 7,000 to 

 10,000 ft. 



6. RUMEX L. 



Weed-like herbs, ours perennial (except no. 9). Leaves mostly in a basal 

 rosette, those on the stem alternate, the petioles with somewhat sheathing 

 stipules. Flowers mostly greenish, sometimes reddish or yellowish, pediceled 

 and borne in usually crowded whorls along the branches of the panicle. Calyx 

 of 6 nearly distinct sepals, the 3 outer spreading or reflexed, the 3 inner larger, 

 continuing to grow after flowering and hugging the achene, 1 or more of them 

 in many of our species bearing a wart or callous grain on the back. Fruits, 

 therefore, more conspicuous than the flowers. Stamens 6. Styles 3, short; 

 stigmas tufted (wind-pollinated) and maturing before the stamens. Achene 

 triangular. (Old Latin name used by Pliny.) 



Leaves hastate; flowers dioecious; sepals without callous grain, not reticulated and not 



longer than the achene; pedicels not jointed; roots red, scentless. — Sorrels 



1. R. acetosclla. 

 Leaves never hastate; flowers perfect or some staminate on the same plant; inner sepals 

 commonly reticulated, in fruit becoming much longer than the achene; pedicels 

 jointed; roots yellow, scented, bitter. — Docks. 

 Tuner fruiting sepals entire (or nearly so) and 



