FIG. 1. Life cycle of the Dictyosteliidae, with special reference to the different patterns
of aggregation. A few of the steps have thus far been observed only in certain of the
species examined. At the top, the later development of the aggregates is recorded without
detail, and only a single kind of stalked fruiting body is drawn. At the bottom are two
patterns of feeding. Many pathways are reversible, and these are shown by lines with
arrowheads at both ends; thus the cells can travel along any path that leads to an arrowhead, even if the path starts with an arrow pointing towards them. On the right at the
bottom three processes are included whose occurrence or relation to the life cycle is
uncertain.