Caltha
L.
Perennial glabrous herbs in marshy and semi-aquatic places; rootstock stout, somewhat rhizomatous, creeping or ascending; roots axillary, fibrous; stems erect, up to 60
cm high, hollow, simple or branched. Leaves alternate, simple or lobed; radical leaves
long-petioled; cauline leaves short-petioled to sessile; lamina oblong-ovate, obovate,
elliptic-oblong, orbicular or reniform-deltoid, often cordate at base, entire, crenate or
closely dentate, up to 25 cm across, glossy, (some species of S. Hemisphere have
appendages at base of lamina). Flowers actinomorphic, yellow, rarely white or pink,
usually in few-flowered loose cymose panicles or corymbs, sometimes flowers solitary
or paired on scapes. Perianth 1-whorled, petaloid; segments 5 or more, alike, Dot
clifferentiated into sepals and petals. Stamens 8-many, on flat receptacle. Carpels (2-)
5 -
10(-25), sessile, free; ovules many on ventral placentas. Follicles oblong, subcompressed. Seeds several in 2 rows along ventral suture, black.
Mostly in northern temperate and arctic regions, some in southern temperate regions; ca 10 species, 2 in India, confined to Himalayan regions.
Literature. HILL, A (1918) The genus Caltha in southern hemisphere. Ann. Bot. (London) 32: 421 - 435. SMIT, P.G. (1973) A revision of Caltha. Blumea 21: 119 - 150.
Mostly in northern temperate and arctic regions, some in southern temperate regions; ca 10 species, 2 in India, confined to Himalayan regions.
Literature. HILL, A (1918) The genus Caltha in southern hemisphere. Ann. Bot. (London) 32: 421 - 435. SMIT, P.G. (1973) A revision of Caltha. Blumea 21: 119 - 150.
KEY TO THE SPECIES
| 1a. Leaves reniform-deltoid, radical and cauline; flowers in corymbs, rarely solitary | 1. Caltha palustris |
| b. Leaves broadly ovate-cordate, all radical; flowers solitary or paired on scapes | 2. Caltha scaposa |
