Fig. 12. Streams of S13A cells late in aggregation fragment. Homogeneous populations of JH10 and S13A-1 cells were video-recorded at low magnification late in aggregation during stream formation. Stream formation and fragmentation are obvious in the S13A-1 cultures. In repeat experiments, S13A-1 and S13A-2 streams formed and fragmented, as in the representative panels in B. Zero minutes represents the time at which video-recording was initiated.