11. Parasagittal section of cerebellar cortex by Ramon y Cajal in 1894. In this drawing, all cell types and afferent fibers are placed in a three-dimensional perspective. Dots represent parallel fibers from granule cells. The cells types and afferent fibers in cerebellar cortex mainly consist of (a) Purkinje cells (PCs); (b,e,f) basket cells which inhibit PCs; (g) granule cells which use "parallel fibers" to excite PCs; (h) mossy fibers which form synapse with granule cells; (n) climbing fibers which form synapse with PCs.
(Image Credit: Constantino Sotelo/Nature Reviews Neuroscience)
Sotelo, Constantino. "Viewing the brain through the master hand of Ramon y Cajal." Nature Reviews Neuroscience 4, no. 1 (2003): 71-77.