Careful inventory work and an improving knowledge of difficult genera led to the discovery of new localities for a number of interesting species like Potamogeton coloratus, Hypericum canadense, Carex flava, Callitriche hermaphroditica, Dryopteris pseudomas and Bromus benekenii. Two new hybrids are reported: Dryopteris x tavelii (all former reports being erroneous) and Carex x tornabenii (= C. distorts x extensa). The neophytes Ajuga pyramidalis and Apera interrupta are now considered to belong to the Dutch flora. Reported for the first time are Bupleurum gerardii and Pastinaca sativa subsp. wens. Puccinellia rupestris and Silene gallica are not extinct. Of Oenanthe crocata, first discovered in 1975, two new localities are found.