The pattern of early neuronal differentiation in Drosophila melanogaster.

Based on the staining of Drosophila embryos with neuron-specific monoclonal antibodies we describe the differentiation of the earliest neurons in the central nervous system. The metameric array undergoes a number of changes during development that distinguish several morphological units: metameres, neuromeres and ganglia. Neural landmarks in the CNS and the periphery are identified on the bases of their developmental history, axonal projection and segment specificity. A time sequence of differentiation starting in the posterior gnathal and anterior thoracic anlage has been found.