The term area 14 of Walker refers to a subdivision of the frontal lobe of the macaque (Macaca) defined on the basis of cytoarchitecture. The cortex is relatively thin with a very thick first, molecular layer, i.e., "at least a third of the thickness of the entire cortex." The thickness of the second layer is normal; that of the third layer is reduced by about half relative to that of area 10 of Walker; the fourth is faintly visible; and the fifth and sixth layers are "extremely narrow." Walker regarded this area as cytoarchitecturally homologous to a portion of prefrontal area 11 of Brodmann-1909 ( Walker-1940 ).