Pathfinding by neuronal growth cones in grasshopper embryos: II. Selective fasciculation onto specific axonal pathways

In the previous paper (Raper, J. A., M. Bastiani, and C. S. Goodman (1983) J. Neurosci. 3: 20-30) we showed that the growth cones of two sibling neurons, the G and C cells, follow the same route in the developing grasshopper neuropil until they reach a stereotypic choice point. Here their growth cones diverge from each other as G turns and extends anteriorly and C turns and extends posteriorly. In this paper we show that the G and C growth cones fasciculate and extend in opposite directions upon a specific bundle of four axons.