A study on Stellaria nemorum L. in the Netherlands was made concerning morphology, geography, ecology and nomenclature. The species has usually been divided into 2 subspecies, the nomenclature of which is dealt with. The correct names appear to be S. nemorum L. subsp. nemorum and S. nemorum L. subsp. glochidisperma Murb. The known area of distribution of subsp. glochidisperma Murb. has been extended into the Netherlands; representative populations of both taxa were found. The two subspecies are mutually different not only in many morphological properties, but also in flowering time and probably in ecological preference. Cultures and breeding experiments were made and are still in progress.