Nieuwe soorten uit het genus Rubus L. uit de binnenduinen

Three new species from the coastal area of the Netherlands are described: Rubus vadalis Beek mainly from the islands in the North, similar to R. platyacanthus P.J. Müll. & Lefèvre, but less hairy; Rubus ceratifolius Beek mainly from the dunes of the west-coast, related to R. gelertii Frid., but with tender pricklets and long pedicels;.and Rubus thalassarctos Beek which frequently occurs in the woods of the islands Texel and Vlieland, belonging to the series Vestiti Focke and characterised by the ternate leaves and very long and dense indumentum.