Landolt's Club in the Amphibian Retina: A Golgi and Electron Microscope Study

¹ Department of Biological Structure, University of Washington Seattle, Wash.

Landolt's club process has been studied in the adult newt retina. In Golgi preparations this process has been shoivn to arise from the dendritic trunk of a bipolar cell and to pass through the external synaptic layer without discernible synapse, apparently to terminate as an enlarged bulb at the level of the external functional zone (external limiting membrane). This confirms Landolt's original observations. The electron microscope reveals, in addition, that this process often lacks intervening glia between its own cell membrane and that of adjacent photoreceptors. Morphologically the club process differs somewhat from a typical dendrite. The process passes through the external functional zone and terminates as a 9+0 cilium which extends between the receptor inner segments