The term area FCBm of Bonin refers to an area of cerebral cortex defined on the basis of cytoarchitecture in the macaque. The area labeled FCBm was described together with area FC of Bonin and area FCop of Bonin as "a zone which surrounds the frontal lobe… anterior to the agranular cortex… which contains but a feeble granular layer." Because of "the tendency for cells of iiic to become prominent," the authors regarded it as homologous to area FCBm of the human as defined by Economo ( Bonin-1947 ).