On the occurrence of Ligularia sibirica in Bohemia.

Traditionally, only two native localities of Ligularia sibirica have been reported from the Czech Republic. In the present paper, a correction is made as to the founder of the locality between Jestřebí and Staré Splavy near Doksy (50°36'23" N, 14°36'54" E) which was discovered by J. Ch. Neumann in 1814 the latest, i.e. earlier than thought. The species has been retreating from this locality because of changes in environmental conditions, with the decrease of groundwater level after amelioration in 1928 being the most important factor. However, the species is not yet endangered in the locality. The second locality is between Bělá pod Bezdězem and Bakov nad Jizerou (50°29'45" N, 14°54'39" E) and it was not discovered by anybody of those reported up to now but by V. J. Sekera; the discovery was not made in 1854 but as early as in 1843. This locality consists of several populations and its size has increased during the last 100 years. Bohemian localities, which are rather distant from the continuous distribution of the species, originated in the early postglacial period (Praeboreal) and represent remnants of former more extensive distribution in this region. The cultivation of the species and its secondary occurrence are rare and mostly unimportant events.