Fig. 3.

Camera lucida reconstruction of a synaptically connected BC–BC pair. Soma and dendrites of the presynaptic BC are drawn in green. Axonal arborization of the presynaptic BC is drawn in red. Soma and dendrites of the postsynaptic BC are drawn in black. Axonal arborization of the postsynaptic BC is drawn in blue. Only the portions of the axons that could be unequivocally traced back to the soma are depicted. Synaptic contacts (confirmed by subsequent electron microscopy; see Fig. 4) are indicated by arrowheads. Additionally, the postsynaptic BC showed three autaptic contacts (confirmed by electron microscopy; data not shown). Note that the axonal arborization of both BCs was largely confined to the granule cell layer, identifying them as BCs. ml, Molecular layer; gcl, granule cell layer.