Cells responsive to stretching individual eye muscles were identified electrophysiologically in the medial dorso-lateral part of the semilunar ganglion of the Lamb. The destruction of such a cellular pool was followed by degeneration of some spindles in those eye muscles whose stretch had elicited responses of the gasserian cells and of some nervous fibers in the ophthalmic branch, in the sensory trigeminal root and in the ipsilateral descending trigeminal tract. The degenerations ended in the pars oralis of the ipsilateral descending trigeminal nucleus. Thus it is clear that the afferent impulses from the eye muscle proprioceptors project on the ipsilateral descending trigeminal nucleus. This is also confirmed by the fact that it was possible to record antidromic evoked potentials from the cellular pool of the medial dorso-lateral part of the semilunar ganglion by stimulating with single pulses the same pontine areas of the ipsilateral descending trigeminal tract which responded to stretch of individual eye muscles.