As a result of an investigation on the variability in morphology, anatomy and cytology in relation to ecological behaviour of the subspecies of Lotus corniculatus L. in the Netherlands, we found subsp. corniculatus as an ecological-plastic taxon with a number of modifications. In subsp. tenuis we could distinguish two ecotypes, respectively of a saltish and a non-saltish habitat. The non-saltish ecotype grows together with the subsp. corniculatus. Furthermore there is a difference between epidermal pattern and stomata of both subspecies (fig. 3 & 4). Moreover differences in the number of chromosomes were found confirming the literature, namely subsp. corniculatus 2n=24 and subsp. tenuis 2n=12. On account of stated ecological, morphological, anatomical and cytotaxonomical differences between L. corniculatus subsp. corniculatus and L. corniculatus subsp. tenuis, both appearing in the dunes of Oostvoorne, one has every reason to take these subspecies as species again, also in the flora of the Netherlands.