Summary
In adult earthworms, the septal membranes separating unicellular giant fibre metameres are absent in most segments, thus resulting in the formation of multicellular neuronal syncytia. The elimination of septa may contribute to a significant reduction in the conduction time along the giant fibres.
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Günther, J. Neuronal syncytia in the giant fibres of earthworms. J Neurocytol 4, 55–62 (1975). https://doi.org/10.1007/BF01099095
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DOI: https://doi.org/10.1007/BF01099095