7. Argythamnia. Petals and sepals 5. Stamens 10–15, united. Styles bifid, linear.
8. Acalypha. Calyx 4- (3–5-) parted. Stamens mostly 8. Fertile flowers in the axils of leafy bracts. Stigmas finely dissected.
9. Ricinus. Racemes terminal, subpanicled. Calyx 3–5-parted. Stamens very numerous; the filaments repeatedly branched. Styles 2-parted.
d. Flowers apetalous, in racemes or spikes pistillate at base. Stamens 2 or 3. Styles simple.
10. Tragia. Flowers racemose. Calyx-lobes valvate in bud. Hirsute or pubescent.
11. Stillingia. Flowers spicate. Calyx-lobes imbricate in bud. Fertile bracts glanduliferous. Glabrous.
1. EUPHÓRBIA, L. Spurge.
Flowers monœcious, included in a cup-shaped 4–5-lobed involucre (flower of older authors) resembling a calyx or corolla, and usually bearing large thick glands (with or without petal-like margins) at its sinuses. Sterile flowers numerous and lining the base of the involucre, each from the axil of a little bract, and consisting merely of a single stamen jointed on a pedicel like the filament; anther-cells globular, separate. Fertile flower solitary in the middle of the involucre, soon protruded on a long pedicel, consisting of a 3-lobed and 3-celled ovary with no calyx, or a mere vestige. Styles 3, each 2-cleft; the stigmas therefore 6. Pod separating into 3 1-seeded carpels, which split elastically into 2 valves. Seed often caruncled (ours only in §§ 5 and 6).—Plants (herbs in the United States), with a milky acrid juice. Peduncles terminal, often umbellate-clustered; in the first section mostly appearing lateral, but not really axillary. (Named after Euphorbus, physician to King Juba.)
A. Glands of the involucre with petal-like, usually white or rose-colored, margins or appendages; these almost obsolete in n. 1.
§ 1. ANISOPHÝLLUM. Leaves all opposite, short-petioled, small, oblique at base; stipules awl-shaped or scaly and often fringed, persistent; stems much branched, spreading or usually procumbent; involucres solitary in the forks or in terminal or pseudo-lateral clusters, small, with 4 glands; seeds ash-colored (except in n. 10); annuals.