Enige aanvullingen op de Flora van Vlieland

The author reports the occurrence of Veronica hederifolia L. (2n = 54) and of Ornithogalum umbellatum L. (2n = 27, 2n = 45) on the West Frisian Wadden island Vlieland. The pentaploids of O. umbellatum flower early and are many flowered, the triploids (2n = 27) are few flowered and flower later. The very rare apomictic heptaploid (2n = 63) cytotype of Hieracium pilosella L. has been found on the Vuurboetsduin near the village Oost-Vlieland. Hieracium peleterianum Mérat and the hybrid with H. pilosella have been recorded erroneously from Vlieland (MENNEMA & VAN OOSTSTROOM, 1975); both are only recorded from Terschelling.