The optic tectum of a perciform teleost. I. General configuration and cytoarchitecture.

Abstract

AbstractGolgi techniques have been employed to study the cytoarchitecture of the optic tectum in the perciform teleost Eugerres plumieri. The stratum marginale (SM) contains abundant fine axons which contact the spiny dendritic tree of large pyramidal neurons of the stratum fibrosum et griseum superficiale (SFGS). Such arborizations arise from a robust, naked apical dendritic shaft. The pyramidal neurons also have a basal dendritic shaft and an axon, both of which ramify in overlapping horizontal fields within the stratum griseum centrale (SGC). The SGC contains fusiform neurons with apical and basal dendritic shafts which ramify horizontally at the SFGS and just above the stratum album centrale (SAC), respectively; an axon “a crosse” originates from the apical shaft. Also in the SGC is the soma of the small pyriform neuron; from it originates a slender dendritic stem which branches out at the SM. Other neurons of SGC and SAC are the small and the large multipolar neurons, and the large pyriform neuron. The large pyriform neurons send a thick dendritic stem which gives horizontal branches mainly at the SFGS, and from which an axon “a crosse” originates. The stratum periventriculare contains small pyriform neurons whose slender dendritic stem ramifies at the stratum opticum as well as at other strata. No axon was seen to originate from these neurons.