557 Nigritella nigra (L.) Rchb. fil.

This boreal-montane, calciphilous species is restricted to Europe. It occurs nowadays less frequently (at least in Sweden) than formerly, when it grew in areas rich in meadows (Björkbäck et al. in Fauna & Flora 71/1976, p. 49 ff.). The Scandinavian and most of the C. European populations seem to be morphologically the same, although differences in reproduction and chromosome number have been demonstrated. In separate parts of C. Europe two subspecies have been distinguished (Fl. Eur. 5/1980, p. 33). Cf. also Meusel et al. 1965, map p. 106.