Diploid populations of Valeriana officinalis L. (Valerianaceae) in Central Europe exhibit an extensive variation, with two conspicuous morphotypes. One, corresponding to the lectotype of V. officinalis, is larger, with broader, distinctly dentate leaflets, the other is in many respects similar to V. pratensis Dierb. and V. stolonifera Czern., but is glabrous, with narrow, usually entire leaflets. The two forms also differ in their ecological optimum and in geographical distribution, but are linked with numerous intermediates.