Printed in Great Britain Evidence for a Substance Responsible for the Spacing Pattern of Aggregation and Fruiting in the Cellular Slime Molds

I N the cellular slime molds, after the individual amoebae have finished their growth and depleted their food supply, they aggregate into centers. Each center ultimately produces a small fruiting body (a spore mass supported by a slender stalk) that rises into the air. In a previous study (Bonner & Dodd