In the mammalian hippocampus. the dentate gyrus (DG) is characterized by sparse and powerful unidirectional projections to CA3 pyramidal cells. the so-called mossy fibers. Mossy fiber synapses appear to duplicate. https://www.roneverhart.com/Brown-Paper-Luncheon-Napkin-Live-Joyfully-13-x-13-500-count-box/