A study of neuron morphology in Aplysia californica using procion yellow dye

1. 1. The morphology of two neurons, L10 and R2, of the abdominal ganglion of Aplysia californica was studied in serial sections after intracellular injection of Procion Yellow dye. 2. 2. The main axons of both cells give off many finer processes ending within a restricted volume of neuropil. 3. 3. The geometry of the major interneuron L10 requires that the processes of distant follower cells converge in this restricted neuropil region. 4. 4. The branching patterns of L10 and R2 do not reflect differences in synaptic output.