When the young medusae swim away from their parent gonzooids, the second generation truly begins. The umbrella shaped creatures have tentacles covered in nematocysts and suctorial pads that assist in capturing prey. Reproduction of Obelia medusae occurs sexually, eggs and sperm uniting to become small larvae surrounded by cilia. Although, beginning as a free moving individual, the larvae eventually settle, each one becoming the founding member of a new polyp colony.