SAUVAGEAU1, from an examination of dried herbarium specimens, concluded that there was evidence that five species of Halopteris were oogamous, the best substantiated case being that of H. hordacea (Harv.) Sauv.2,3. No observations have hitherto been made on living plants of this species or on any of the other southern species suspected of oogamy. Using simple sea-water cultures, Sauvageau's findings have been confirmed in an intertidal form agreeing with H. congesta (Rke.) Sauv. and in a species from deeper water, presumably H. funicularis (Mont.) Sauv. Both species are common on the Wellington shores of Cook Strait, and, although asexual plants greatly predominate, sexual plants have been found in both winter and summer.