A preparation of the stick insect Carausius morosus for recording intracellularly from identified neurones during walking

Using a preparation of the stick insect it is possible to record activity from the neuropile of the mesotheoracic ganglion during sequences of walking behaviour lasting several minutes. The animal walks on two lightweight wheels, counterbalanced to give an upthrust of 0.4 g against the legs. Each wheel may be rotated independently during turning behaviour. The walking behaviour of the operated preparation is compared with the results obtained for free‐walking animals, and intact or partially operated preparations, walking on heavier wheels and mercury. Records from several identified retractor motor neurones show the stability and reproducibility obtainable with this preparation.