PHOSPHATE ACCUMULATION BY COLONIES OF NOSTOC

1. Evidence was obtained which supports the hypothesis that thefirm colonies of Nostoc verrucosum, but not the softer onesof N. commune, can accumulate phosphate from the environmentby non-active means.
2. This accumulation of phosphate was reducedby pre-treating thecolonies with chelating agents, whilst thepresence of CaCl₂in the medium led to an increase.

(Received February 2, 1967; )