THE NERVOUS-SYSTEM OF PROCERODES LITTORALIS (MARICOLA, TRICLADIDA) - AN ULTRASTRUCTURAL AND IMMUNOELECTRON MICROSCOPIC STUDY

The ultrastructure of the nervous system of a planarian, Procerodes li ttoralis, belonging to the taxon Maricola is described for the first t ime. The study has revealed the presence of two neuronal cell types an d a glia-like cell. Immunogold labelling with antibodies to two native flatworm neuropeptides-neuropeptide F and GNFFRFamide-has been locali sed to one neuronal cell type and associated processes and synapses, t hus indicating its peptidergic nature. The ultrastructural features ar e compared to those of other investigated turbellarian species. The nu mber of features shared by species from the Proseriata, Lecitoepitheli ata and Tricladida show that in respect of the nervous system these ta xa form a closely related group. (C) 1997 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd.