Abstract:By continuous observation of embryonic development and podocyst propagation of Jellyfish, Rhopilema esculentum , two generation modes of scyphistoma were discovered. Mode Ⅰ, fertilized egg turned to scyphostima, which process took about 6 h from fertilized egg to planulae, and then nearly 25 h from planulae, scyphostoma to stationary scyphistoma with four tentacles at the temperature of 26±1℃; Mode Ⅱ, podocyst generated to scyphostima. The ratio of generation became higher with podocyst closed to scyphistoma. In this stage, podocyst first turned into scyphostoma, and then became scyphistoma with four tentacles. In this study, a new structure called scyphostoma was both found in the two scyphistoma generation modes. This discover improved the life cycle of jellyfish.