Sensory responses and axonal morphology of two different types of cerebral neurones in Helix pomatia L.

1. The mechano- and chemosensory responses of two different types of cerebral neurones responding to food stimuli were studied by microelectrophysiological techniques. This was correlated with axonal morphology investigated by intracellular Co-lysine labelling. 2. The C4 neurone responded to food stimuli applied to the lip receptors by phasic (less than 30 sec duration), while the C14 neurone by an initial phasic and a subsequent tonic longer than 10 min duration) activity change. 3. The different sensory responses of the two neurones can partly be explained by the morphological differences found between them.