In recent years several new bryophyte species could be added to the flora lists of the Wadden Sea Islands of Texel and Vlieland. The most remarkable of these new finds was the Mediterranean-Atlantic moss Bryum provinciale Philib., which formerly reached its northeasternmost limit of distribution in Belgium, but has apparently been spreading into the calcareous sand dunes in Holland in recent years, see als Kruijsen & Damm 1997. The present paper also contains a report on the ascomycete Bryostroma trichostomi (Roll.) Döbb., a new species for The Netherlands, which was discovered as a parasite on Didymodon vinealis (Brid.) Zand. in the Texel sand dunes.