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Material from localities in N. Scania, Sweden, was used in the present investigation. The chromosome number was 2n=56 in P. intermedia (as previously counted in Polish material) and 2n=70 in P. norvegica (as in many previous counts). Crossing experiments indicated pseudogamy in both species. Apomictic reproduction has been reported previously in P. intermedia, while P. norvegica has been supposed to be sexual. Embryologic studies gave evidence of obligate apospory in P. intermedia, while in P. norvegica some of the primary EMC:s undergo meiosis. In the latter species, partial sexuality is not quite excluded, although it reproduces mainly by apomixis. Meiosis on the male side is fairly irregular in P. intermedia while on the other hand P. norvegica has a quite regular bivalent formation, in spite of its high degree of polyploidy. P. intermedia is supposed to be of hybrid origin, being the result of crosses between P. argentea and P. norvegica. This remains to be proved experimentally, however, since crossing experiments between P. argentea and P. norvegica have so far failed to give any offspring.