VARIATION IN OCHLOCHAETE HYSTRIX (CHAETOPHORALES, CHLOROPHYCEAE) STUDIES IN CULTURE.

Six different isolates of Ochlochaete Thwaites ex Harvey have been studied under identical culture conditions. All the isolates show open branching, a character previously ascribed specifically to O. hystrix Thwaites ex Harv, sensu sticto, and all form hair on rounded cells in the central part of the thallus, a character hitherto attributed only to O, ferox Huber. Consequently, separaton of these two entities on the species level is untenable. The plant described by Huber is referred to O. hystix varferox (Huber) var. nov. The type material of Chaetobolus gibbus Rosenvinge is similar to one of the isolates studied and is included in O. hystrix. Quadriflagellate zoospores have been observed in all the isolateds, and in one of them also biflagellate swarmers. [ABSTRACT FROM AUTHOR]