The purpose of this study is to present a detailed and accurate description of the morphogenesis and histogenesis of the muscles in man supplied by the facial or seventh cranial nerve together with the morphogenesis of the extramedullary part of the nerve. The muscles include not only those of facial expression but also the nonmimetic muscles. The development of the facial nerve encompasses the formation of its roots, geniculate ganglion, branches, interanastomoses and anastomoses with other nerves. Such a study may be helpful in understanding and explaining variations and anomalous arrangements of the facial musculature and nerve, fetal reflexes and general patterns of development in the head and neck region.