Erratum.
In the Research News article by Jean L. Marx, "The polyphosphoinositides revisited" (19 Apr., p. 312), the discovery of inositol 1,3,4-tris-phosphate was erroneously attributed to Michael Berridge of Cambridge University. Although Berridge presented some of the data at the Smith Kline & French symposium, the work was actually done by his Cambridge colleagues Robin Irvine and Peter Downes.