Elatine L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 295-296

2. Elatine L. 2

Herbs of wet places. Leaves entire. Sepals 3 or 4, membranous, obtuse, connate at base. Petals 3 or 4, membranous, patent in terrestrial plants, closely investing ovary or occasionally absent in aquatic plants. Capsule more or less globose. Seeds straight or curved.

Literature: G. Moesz, Magyar Bot. Lapok 7: 1 -34 (1908). H. Glück in A. Pascher, Die Süsswasser-Flora Mitteleuropas 15: 299-313. 1936. H. L. Mason, Madrono 13: 239-240 (1956).

Many authors have regarded the presence or absence of the pedicel as an unreliable character but cultivation experiments (Mason loc. cit.) suggest that this character is constant within each species.

All species grow in shallow, usually still water, on wet mud or sand, or in seasonally flooded places. 1 Leaves in whorls of 3-18 1. alsinastrum 1 Leaves opposite 2 Flowers 4-merous 3 Sepals about 3 times as long as petals at anthesis 4. hungarica 3 Sepals not or little longer than petals at anthesis

4 Sepals shorter than mature capsule 2. hydropiper 4 Sepals longer than mature capsule 3. macropoda 2 Flowers 3-merous 5Stamens 3 6 Flowers sessile; capsule remaining in leaf-axil at maturity

5. triandra 6 Flowers shortly pedicellate; capsule turning away from leaf-axil at maturity 6. ambigua 5Stamens 6 7 Flowers sessile, in axillary cymes of 2-5 8. brochonii 7 Flowers pedicellate, solitary in leaf-axils 7. hexandra