Fig. 7.

DiI/DiO mapping of occipital neural crest cell versus lateral mesoderm cell movements. Dorsal or lateral views of chicken embryos as in Fig. 5. (A–D) Tracing of neural crest cells (ncc). (A) Labelling of the neural folds overlying somites 1, 3, and 5 with DiI and DiO at HH8. (B) At HH12, nnc from the levels of somites 1 and 3 are actively migrating laterally; cells from the level of somite 5 have started their migration. (C, D) At HH16-18, ncc from somite level 1 fill the caudal pharyngeal arches, ncc from the level of somite 3 navigate around the most caudal arch (arrows), ncc from somite level 5 remain caudal to the ncc population from somite level 3 (open arrowhead). (E–H) Tracing of ncc originating from somite levels 3–4 with DiI and lateral mesoderm from somite 1 levels with DiO. (E) Labelling of cells at HH8-10. (F) At HH12, the lateral mesodermal cells have moved laterally–ventrally (arrowhead), the ncc are following behind (arrow). (G, H) At HH16-18, the lateral mesodermal cells move rostrally along the floor of the pharynx (arrowheads), closely followed by the ncc (arrowheads). Abbreviations: ma, mandibular arch and ov, otic vesicle.