The aim of this investigation was to analyse in nembutalized and curarized lambs a somatotopic organization of extraocular muscle proprioceptive afferents in the superior colliculus. Responses to moderate manual stretch on individual eye muscles were recorded by means of tungsten microelectrodes, along the dorso-ventral axis in the superficial layers of the superior colliculus. The mesencephalic representation of the eye muscle proprioception was somatotopically arranged in the following manner: the inferior rectus and the inferior oblique were represented in the most dorsal layer of the superior colliculus, while the superior rectus and the superior oblique projected in the intermediate layer and the lateral and the medial recti in the deepest layer. Our findings indicate for the first time that a somatotopic arrangement of the eye muscle proprioception is present in the superior colliculus as in the semilunar ganglion and in the pontine trigeminal nuclei. The significance of this projection is discussed in relation to the oculomotor proprioceptive behaviour, visual processes and head movements.