Differentiation, extent and layering of amacrine cell dendrites in the retina of a sparid fish.

The morphology of amacrine cells has been studied in Golgi-stained retinae of the salt water sparid Boops boops. The great variety of size and shapes of amacrine cells has been organized into five classes according to the qualitative parameter 'dendritic architecture', which describes the number, size, course, degree of dichotomy, and varicosity of dendrites. Extent of dendritic field and depth of stratification in the inner plexiform layer, viewed as quantitative variations of a given cell type morphology, complete the criteria for classification. Each amacrine cell is unequivocally defined by a three element code according to the values assumed by the parameters used for the classification. The possible functional implications of dendritic morphology are briefly discussed.