The mosaic of the uncrossed retinal projection in the superior colliculus of the cat.

The uncrossed retinocollicular projection in the cat was labeled by axonal transport of horseradish peroxidase from the eye and visualized in tangential sections through the superior colliculus. The terminals of this pathway are distributed in clusters and form a mosaic pattern rather than stripes in the superficial collicular layers. It is suggested that the periodicity of this pattern relates to the smallest receptive field diameters across the visual field.