Reciprocal connections between the caudal vermis and the vestibular nuclei in the rabbit.

The termination of secondary vestibulocerebellar mossy fibers and the localization of Purkinje cells giving rise to corticovestibular projections were visualized simultaneously in lobules IX and X after injections of wheat germ agglutinin-horseradish peroxidase in the vestibular nuclei of the rabbit. Vestibulocerebellar mossy fibers from the medial, descending and superior vestibular nuclei terminate in longitudinal strips in the granular layer, which coincide exactly with the localization of the labeled Purkinje cells.