976 Thlaspi alpestre L.

This variable European species s. lat. includes some closely related taxa (cf. Fl. Eur. 1/1964, p. 319). It has recently been introduced into N. Europe and naturalized there. Three closely related extra-European taxa are also mapped, viz. T. cochleariforme DC. in N. and C. Asia and Ural (isolated), T. arcticum Pors. occurring rarely in northwestern N. America, and T. montanum A. Nels. in western N. America. Cf. also Meusel et al. 1965, map p. 180.