We report about 8 patients all showing a nystagmus rotatorius or giratoire and differences of the horizontal component. In syndroms of the nervous system monocular nystagmus was combined with a scew-deviation or tremor of the lids. Similar to the syndroms of the fasciculus longitudinalis posterior defects in smooth or quick movements on both sides were different. After operation of a congenital cataract a vertical mystagmus was transformed in a nystagmus latens. In congenital squint syndroms monocular vertical nystagmus may be seen if one eye or both are closed. Separate pathways from the vestibular system only lead to the vertical-moving muscles of one eye.