Neuronal architecture of on and off pathways to ganglion cells in carp retina.

Bipolar, amacrine, and ganglion cells of carp retina, stained intracellularly with Procion yellow, can be divided into types a and b, according to the destination of terminals and dendritic trees in the inner plexiform layer (sublamina a and b, respectively). Type a cells showed hyperpolarizing, or off, responses and type b cells depolarizing, or on, responses. Carp thus resembles cat in the basic organization of on and off pathways in the retina.