Cultures of Gracilaria verrucosa were established from both carpospores and tetraspores in unialgal cultures. Spores of the former gave rise to mature tetrasporophytes. Development of tetraspores resulted in gametophytes with either antheridia or cystocarps in an approximate ratio of 1:1. Mature antheridia formed on gametophytes cultured singly, but cystocarps failed to develop under these conditions. Tetraspores and carpospores from plants in culture were viable, and formed reproductive mature plants of the alternate generation, thereby completing the life cycle.