Fig. 3. Sequential time-lapse images depicting cell behaviors underlying the formation of a Pax3-induced columnar cell arrangement. Tracings of cells from selected intervals (A,B) revealed that cell rearrangement occurred by means of cell migration and cell intercalation. (B) Tracing of cells in A 10 hours later. Products of cell division are indicated by the letters a and b. The cell labelled N indicates a new cell that migrated into the field.