Erratum.
In the announcement of the Gordon Research Conferences by A. M. Cruickshank (4 Mar., p. 1095), under the heading "Fertilization and the Activation of Development" (p. 1108), four listings under the topic "Gamete recognition and binding II" on 2 August were incorrectly printed. They should have read, "Michael G. O'Rand, (subject to be announced); Bayard Storey, ;Reactions between sperm and zona pallucida leading to fertilization in the mouse'; Bonnie S. Dunbar, (subject to be announced); Paul Wasserman, ;Egg surface glycoproteins that regulate mammalian fertilization.' " Under the heading "Hormone Action" (p. 1112), two listings under the topic "Prolactin" on 9 August were incorrectly printed, and one was omitted. They should have read, "Henry Friesen, ;Prolactin receptors'; Paul Kelly, ;Second messenger for prolactin'; Jeffrey Rosen, ;Prolactin regulation of casein genes.' "