Orchis purpurea Huds., Fl. Angl.: 334 (1762).
Homotypic Synonyms:
Orchis miliratis var. purpurea (Huds.), Fl. Angl., ed. 2: 384 (1778).
Orchis purpurea f. vulgaris Leimbach in H.Potonié, Ill. Fl., ed. 3: 140 (1887), nom. inval.
Description:
A tall tuberous perennial, 20-100 cm. high. Tubers 2, ovate, 3-6 cm. long, that of the current year brown and withered at time of flowering, without roots at the apex, that for the next year turgid and ivory-coloured with a few unbranched fleshy roots without root-hairs arising in a circular crown from the apex. Stem stout, 0 4-0 9 (average 0.6) mm. in diam. Leaves large, 2-5 cm. wide, ovate-lanceolate, rather acute, with sheathing base, rather thin and soft, the upper stiffer, all brittle, deep shining green above, rather glaucous, with 10-20 darker veins below; lower leaves forming a basal rosette, upper successively more keeled and clasping, sometimes with a small leafy bract above the uppermost leaf. In woodland plants the lower leaves are darker than the upper, while in plants from open scrub all the leaves tend to be paler, more obtuse and of firmer texture. Flowering raceme long and lax, or, in plants from open scrub, short and dense; bracts minute. Sepals 3, ovate, acute, forming a helmet over the stigma and anther, green throughout, but heavily flecked with small purple patches due to an anthocyanin pigment. Upper petal (actually the lowest, owing to the twisting of the pedicel) forming a pale pink or white labellum with numerous raised crimson papillae, each formed of acutely pointed cells with red sap, divided into narrow upper lobes, two broad squarish lower lobes and a short triangular median tooth. Spur pale pink, about half as long as the ovary. The two other petals narrow, strap-shaped, papillose like the labellum. Ovary about 2-5 cm. long, obovate-fusiform, green, glossy, bearing three longitudinal ribs. Fruit obovate, 2-5-3 cm. long, 05-07 cm. in diam., dehiscing by three longitudinal slits. Seeds very numerous, 0-5-0-7 mm. long, fusiform, consisting of a thin papery testa enclosing a central globular undifferentiated embryo of a few cells only.
Habitat:
Thin calcareous soils, typically over chalk but also on clay, ragstone and Carboniferous limestone; in open Corylus, Fraxinus or Fagus woodland and scrub and, more rarely, in open grassland.
Distribution:
Europe to C. Turkey, NE. Algeria.
