942 Arabis alpina L.

Within this arctic-montane species two subspecies are distinguished, viz. subsp. alpina and subsp. causasica (Willd.) Briq. The northern distribution of subsp. alpina is amphi-atlantic (Hultén, Amphi-atl., p. 50 and map 31). At lower latitudes closely related taxa occur, int. al. subsp. causasica (Willd.) Briq. (syn.: A. albida Stev.) in the Mediterranean region and adjacent areas eastwards, other taxa in the Himalayan region and eastwards and, outside the map area, still other taxa on the E. African mountains. Cf. also world map in Meusel et al. 1965, p. 190.