The fine structure of the reconstructed neural retina of chick embryos.

The fine structure of reconstructed neural retina formed from dissociated neural retinal cells of 6^-day-oId chick embryos on the chorio-allantoic membrane of chick embryos was examined with the electron microscope. Three nuclear layers (ganglion cell Jayer, inner and outer nuclear layers) and two fibrous layers (inner and outer plexiform layers) are found within the reconstructed retina. Both the outer and the inner limiting membranes of the reconstructed structure are constituted from the processes of differentiated Miiller cells. The ganglion cell layer consists of two types of cell, though a typical ganglion cell with axonal process is not observed. Optic nerve fibres are not formed. Amacrine cells are recognized within the inner nuclear layer. Differentiation of the inner segment of the photoreceptor cell occurs, but not of the outer segment. Synaptic structures are recognized in the inner plexiform layer, but not in the outer plexiform layer.