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DescriptionThis plant is a summer annual forming a mat of branching leafy stems up to 2' across. The stems are light green, pale red, or nearly white; they are terete, hairy, and slightly succulent. The stems are slightly swollen where the stipules of the leaves occur. Pairs of opposite leaves occur at intervals along the stems. Individual leaf blades are 3-11 mm. long and 2-6 mm. across; they are broadly oblong or ovate-oblong in shape and finely toothed along the upper margins. Leaf venation is palmate, although only the central veins are conspicuous. The upper blade surface is dull medium green and hairless to slightly hairy, while the lower surface is pale green to white and hairy. The tips of leaf blades are well-rounded, while their bases are rounded to slightly cordate and often asymmetric. Sometimes the margins of the leaf blades are tinted red. The short petioles are light green to nearly white and usually hairy. Small clusters of 1-4 inflorescences develop from the axils of each pair of leaves. Each inflorescence is about 2 mm. across, consisting of a cup-like cyathium on a short stalk that contains a single pistillate flower on a short stalk and 4 staminate flowers. Each cyathium is light green and glabrous to slightly hairy; there are 4 red nectar glands with whitish petaloid appendages along the upper rim of each cyathium. The pistillate flower consists of a 3-lobed ovary with a divided style at its apex; the ovary is light green (while immature), ovoid-globoid in shape, and its lobes have spreading hairs. The stalk of the pistillate flower curves sideways or downward initially, but it later becomes erect at maturity. A staminate flower within the inflorescence consists of a single stamen. The blooming period occurs from mid-summer into fall for about 2 months. At maturity, the ovaries develop into 3-celled seed capsules; each cell of a capsule contains a single seed. The seeds are distributed, in part, by mechanical ejection. Individual seeds are about 1.0 mm. in length, oblongoid-rectangular in shape, and transversely ridged. The root system consists of a slender taproot that branches. The foliage of this plant contains a milky latex.