Fig. 1. A schematic drawing of seam-cell lineages. Ten seam cells in a freshly hatched worm (top) will produce 16 seam cells of the adult. The lineage of the tail seam cell T is not shown. Blue circles represent anterior daughters that fuse with the hyp7 syncytium and green diamonds denote stem seam cells. Pd indicates descendants of the V5.pa cell forming the postdeirid. Anterior is to the left. Based on Sulston and Horvitz (Sulston and Horvitz, 1977).