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In the mammalian retina, 10–12 different cone bipolar cell (BC) types decompose the photoreceptor signal into parallel channels [1–8], providing the basis for the functional diversity of retinal ganglion cells (RGCs) [9]. BCs differing in their temporal properties appear to project to different strata of the retina's inner synaptic layer [10, 11], based on somatic recordings of BCs [1, 2, 4, 12–14] and excitatory synaptic currents measured in RGCs [10]. However, postsynaptic currents in RGCs are influenced by dendritic morphology [15, 16] and receptor types [17], and the BC signal can be transformed at the axon terminals both through interactions with amacrine cells [18, 19] and through the generation of all-or-nothing spikes [20–24]. Therefore, the temporal properties of the BC output have not been analyzed systematically across different types of mammalian BCs. We recorded calcium signals directly within axon terminals …