Abstract
The typification of the marine siphonous green algae Caulerpa prolifera (Forsskål) J.V. Lamouroux (≡ Fucus prolifer Forsskål) (Caulerpaceae), including f. obovata (J. Agardh) Weber-van Bosse and f. zosterifolia Børgesen, is discussed. Original material conserved in the Natural History Museum of Denmark (Copenhagen) at C (Herbarium Forsskålii) and in the Botanical Museum of Lund University at LD are designated as the corresponding lectotypes.