[Avesicular intercellular contacts in the neuropil of the ganglia of the subpharyngeal complex and in the nerves of the edible snail].

Intercellular interconnections in neuropil of dorsal ganglia in the subpharyngeal complex and nerves have been studied in a mature snail (Helix pomatia), dimensions of the shell--3.0 X 3.5 sm, after double fixation (glutaraldehyde and osmium tetraoxide) and treatment with phosphoric tungsten acid. Zones of the neuropil in the left pleural and parietal ganglia have been investigated--where the nerves leave ganglia and in the area of giant cells; neuropil of the central part of both parietal ganglia; central part of the visceral ganglion and nerves--left palial, intestinal and left pleural commissure. The most spread forms of avesicular intercellular contacts in the neuropil are symmetrical. Besides the latter, processes of the neuropil form fissural and desmosomal junctions. Localization of the avesicular contacts supposes presence of dendro-dendritic junctions of desmosomal and fissural types and axo-axonal ones--of desmosomal type. Various types of the contacts differ from each other by their ultrastructural organization.