The term area 22a of Vogts refers to an area of the cerebral cortex of the guenon that is defined on the basis of cytoarchitecture and myeloarchitecture. It is divided into three parts: area 22a alpha of Vogts, area 22a beta of Vogts and area 22a gamma of Vogts. The authors regarded it as topologically homologous to area 22 of Brodmann (guenon) and area 22 of Mauss. They did not define an area 22b ( Vogts-1919 ).