Citation: Gray, Nat. arr. Brit. Pl. 2:720 (1821).

Derivation: Greek batrachos, a frog; in allusion to the aquatic habit.

Synonymy: Not Applicable

Common name: None

Description:
Aquatic annuals or perennials, glabrous or almost so; stems branching, herbaceous; leaves mostly cauline, alternate, submerged and finely dissected into capillary segments or floating and with a lobed or partite lamina, or with both kinds of leaves; stipules membranous, laterally partly adnate to the petiole.

Flowers solitary, terminal, seemingly leaf-opposed along the stems (sympodial growth); sepals 5, light-green, in some with blue tinge, caducous, sometimes deflexed before falling, shorter than the petals; petals usually 5, white (in all but 1 species), matt above, with a yellow claw (in all but 1 species); nectary pit small, bordered by a lunate, circular or pyriform ridge; achenes 4-90, more or less globose to broadly obovoid.

Pericarp on lateral walls with regular transverse ridges 0.05-0.1 mm apart, glabrous or hairy; beak caducous (in all but 1 species); torus globular to pyriform, in some species enlarged in fruit.

Distribution:  About 20 species, almost cosmopolitan but predominantly in Eurasia, North Africa and North America, South Africa and south-eastern Australia (probably introduced).

Biology: No text

Author: Not yet available