Fig. 5

Selected tracings of individual cells from the animal half of the embryo. The cells indicated on top of each column are marked red in the schematic representation and the descendants of the respective cells are seen in red in the lower rows. The intermediary Differential interference contrast image shows the cell divisions and cell movements of the respective cells. Numbers are minutes post fertilization. Nomarski images are all in the same orientation. Axis orientation labels in images indicate orientations: a anterior, a _n animal, d dorsal, l left, p posterior, r right, v vegetal, v _e ventral. Upper panel: Oikopleura dioica. Lower panel: Phallusia mammillata. The right-most column details the mitotic history of cell line a9.49 that has been hypothesized to be homologous to vertebrate neural crest cells