Prof. Dr. K. U. Kramer (Zurich) kindly pointed out that the name Equisetum telmateia Ehrh. var. nanum was invalidly published because no type specimen was indicated (Van Hoek 1979). The type specimen of Equisetum telmateia Ehrh. var. nanum Van Hoek is deposited in the Rijksherbarium at Leiden (L) as Van Hoek 1.