Анотація:
The buccal ganglia of Planorbis corneus was investigated by cytological and neuro-histological methods. It was found that this first shaped sympathetic ganglion, as to the cytological peculiarities of the neurons — localization of organoides and unstable incorporations — and cytochemical reactions does not differ from neurons of the central ganglia of the given mollusk. The predominance of bipolar and multipolar neurons as well as small volume and primitive structure of neuropil are peculiar features of a buccal ganglion. Besides, the terminal plexi of varicose (sympathetic) fibre forming axo-axonal and axosomatic contacts are more frequently met in buccal ganglia than in central ones.