Retinal ganglion cell projections to the superior colliculus of the hamster demonstrated by the horseradish peroxidase technique.

After a localized injection of horseradish peroxidase into the superior colliculus of the golden hamster, retinal cells of all sizes, except the very smallest, were labeled. Since the smallest cells were probably glia or interneurons, these results indicate that in the hamster all retinal ganglion cell types project directly to the contralateral superior colliculus. This finding is in agreement with recent physiological studies dealing with the conduction velocities of retinocollicular axons in the hamster.