Reciprocal connections between the 'nucleus rotundus' and the dorsal lateral telencephalon in the weakly electric fish Gnathonemus petersii.

Injections of horseradish peroxidase into the dorsal lateral telencephalon of the weakly electric mormyrid fish Gnathonemus petersii resulted in retrogradely filled cells and anterogradely labelled terminals in the 'nucleus rotundus' of the ipsilateral rostral diencephalon. This connection courses via the lateral part of the lateral forebrain bundle. The present results suggest a particularly close relationship between the Dla cell group of the lateral telencephalon and the 'nucleus rotundus'.