1. Parnassia Linnaeus, Sp. Pl. 1: 273. 1753; Gen. Pl. ed. 5, 133. 1754.
Grass of Parnassus, bog star, parnassie [Greek Parnassos, alluding to fabled origin on slopes of Mount Parnassus] Grass of Parnassus, bog star, parnassie [Greek Parnassos, alluding to fabled origin on slopes of Mount Parnassus]
Peter W. Ball
Herbs, perennial <with caudices or rarely rhizomes>. Stems erect, unbranched <scapelike>. Leaves basal <in rosettes or 1–2 per node on rhizomes (P. caroliniana)> and cauline <(0–)1[–8]>, alternate; stipules absent; petiole present in basal leaves, usually absent in cauline leaf; blade margins entire; venation palmate. Inflorescences terminal, flowers solitary. Flowers bisexual, radially symmetric or ± asymmetric; perianth and androecium hypogynous or perigynous; hypanthium absent or completely adnate to ovary; sepals 5, connate proximally; petals 5, white [yellowish] with distinct yellowish or greenish or gray-brown veins, <3–22 mm, usually longer than sepals>; nectary absent; stamens 5; staminodes 5, opposite petals, usually deeply divided, sometimes undivided, gland-tipped or glandular at apex [without glands]; pistil [3–]4[–5]-carpellate; ovary superior to 1/2 inferior, 1-locular, placentation parietal; style absent or essentially so; stigmas [3–]4[–5]; ovules 100–2000+. Fruits capsules, 1-locular, <[3–]4[–5]-valved>, ellipsoid to globose, apex not beaked. Seeds 100–2000+ per fruit, oblong, winged; aril absent. x = 9.
Species ca. 70 (9 in the flora): North America, Mexico, Europe, Asia, nw Africa.
The North American species of Parnassia usually occur in moist to wet sites on neutral to base-rich substrates, but P. asarifolia often occurs on acidic substrates.
The treatment of Parnassia cirrata and P. fimbriata follows that proposed by R. B. Phillips (1980).
SELECTED REFERENCE Phillips, R. B. 1980. Systematics of Parnassia L. (Parnassiaceae): Generic Overview and Revision of North American Taxa. Ph.D. dissertation. University of California, Berkeley.