1970 年 83 巻 986 号 p. 270-280
The sexual and asexual reproduction, development and cytology of a marine alga, Anadyomene wrightii have been studied by culture experiments. The plants produced and liberated swarmers at 23°, 2500lux, 14hr light, 10hr dark condition. There are three types of plants; one is sporophyte, producing quadriflagellate zoospores and the other two are male and female gametophytes, forming biflagellate isogametes. These three plants are superficially similar and can not be distinguished from one another. The gametes from the same thallus do not fuse, but the copulation takes place between those from thalli of different sex. The mode of the germination of zoospores is similar to those of the zygotes. It is of the so-called “Typus filamentosus immediatus”. showing bipolar nature. The method of septation of the germlings is not of the segregation, but of the centripetal formation. The somatic chromosome number of germlings derived from the zoospores is 12- 15, and those derived from the zygotes is 25-30. The shape of zoospore and gamete, the mode of germination, the type of the alternation of generations and the manner of septum formation, all support the circumscription that the Anadyomenaceae is a taxon belonging to the Cladophorales.