Fig. 5. Early development of the PP nerve. Each panel shows one or more hemiganglia on the right side of a germinal plate in which the N lineage was labeled with RDA. (A) A series of three hemiganglia (65-70 hours clonal age), from a preparation that was also immunostained for ACT (green), reveals the close association of the developing PP nerve (arrows) with the laterally migrating nz1 and nz2 axons (arrowheads). (B) A single hemiganglion at the same age from a preparation in which the O lineage was labeled with FDA lineage tracer (green). There is a close association between processes originating from the P_D neuron (arrow) and the peripheral oz2 and/or oz3 neurons (lower arrowhead). O-neurons P_D, oz2 and oz3 are coincident with the PP nerve and the latter two (oz2 and oz3) are closely associated with N-derived neurons nz1 and nz2 (overlap appears yellow). Anterior is upwards. Scale bar: 25 µm.