In cat retina, antisera directed against tyrosine hydroxylase (tyrosine 3-monooxygenase; EC 1.14.16.2) labeled three morphologically distinct classes of neurons; amacrine cells, displaced amacrine cells, and interplexiform cells. These three cell populations differed not only in their morphologies but also in their numbers, densities, and retinal distributions. Insofar as tyrosine hydroxylase-like immunoreactivity is associated with dopaminergic neurons, these observations suggest that the dopamine system in cat retina is morphologically heterogeneous and that the cat retina contains functional subdivisions based on the different distributions of specific cell populations.