Thanks are due to Dr B.Meyer for identification of the organism as A.ovalisporum
and to Prof. J.Komarek for the reconfirmation. We are grateful to
S.Chava, E.Feldman, T.Fishbein, J.Graham, M.Hatab, B.Kaplan and N.Koren for
their assistance both in the laboratory and on the lake. We also acknowledge the
useful comments from an anonymous reviewer.