The projection of the posterior knee joint nerve to the cerebellar cortex.

1. In decerebrate cats, electrical stimulation of the posterior knee joint nerve evokes in the depth of the cerebellar cortex field potentials which have been identified as due to both mossy and climbing fibre inputs.2. The potentials evoked through the mossy fibres have a latency of 15-17 msec and are more widespread. Those evoked through the climbing fibres have a latency of 26-33 msec and are more restricted.3. Stimulation of the larger fibres originating from the Golgi receptors gives only a very restricted projection. When the fibres originating from the Ruffini receptors are also activated, the effect on the cerebellar cortex is more widespread.4. The results have been confirmed by recording unitary activity.