Creeping or ascending, branched small leafy annual glabrous herbs, with opposite obovate oval or orbicular sessile entire leaves, and minute white or purplish short-peduncled flowers, solitary in some of the axils. Calyx 4-5-lobed or 4-5-parted. Corolla very irregular, the tube short, the upper lip shorter than the lower, or wanting, the lower 3-lobed, spreading or ascending, the middle lobe the largest. Stamens 2, anterior; filaments short, somewhat dilated or appendaged at the base; anthers small, their sacs distinct, parallel, or slightly divergent. Style short; stigma 2-lobed. Capsules globose, 2-celled by a membranous partition or becoming 1-celled. Seeds several or numerous, minute. [Greek, small flower.]

About 16 species, natives of America. Besides the following, another occurs in the southern United States. Type species: Micranthemum orbiculatum Michx.

1. Micranthemum Micranthemoides (Nutt.) Wettst. Nuttall's Micranthemum

Fig. 3792

Hemianthus micranthemoides Nutt. Journ. Acad. Phil.

1: 119. pl. 6. 1817. Micranthemum Nuttallii A. Gray, Man. Ed. 5, 331. 1867. Micranthemum micranthemoides Wettst. in Engl. &

Prantl, Nat. Pfl. Fam. 4: Abt. 3b. 77. 1891.

Somewhat fleshy; stem filiform, creeping, the branches ascending, i'-2i' high. Leaves obovate to oval, obtuse, \"-2\" long; flowers about 1/2" long, borne on peduncles of about the same length; calyx campanulate in flower, obovoid in fruit, 4-lobed, usually split along one side; peduncles recurved in fruit; upper lip of the corolla nearly obsolete; middle lobe of the lower lip longer than the lateral ones; appendages at the bases of the stamens nearly as long as the filaments; capsule obovoid-globose, 1/2" in diameter, as long as the calyx.

In tidal mud. New Jersey to Florida. Aug.- Oct. This species is the type of the genus Hemianthus Nutt., which has been regarded as distinct from Micranthemum by other authors, a view which may be maintained.