FIG. 4.

Fruiting body development in M. xanthus. Scanning electron micrographs of cells starved in submerged culture were made by Kuner and Kaiser (69) and are reprinted here with permission. Times poststarvation are indicated in the upper left corner of the first five frames, to which the 10-μm scale applies. Individual cells (about 5 μm long) begin to aggregate by 4 h and complete mound formation by 24 h, at which time some cells have begun to differentiate into spores. The lower right frame shows a mature fruiting body that has cracked open, revealing its spores (5-μm scale).