In the first paper of this series Fulton, Liddell and Rioch1demonstrated in the cat that the cerebral hemispheres are responsible for the genesis of cerebellar tremor. They found that after decerebellation the tremor appeared only when the voluntary movements became reestablished and that removal of the cerebral hemispheres subsequent to decerebellation abolished tremor in the extremities opposite to the cerebral lesion; marked extensor rigidity also came on immediately after the cortical ablation. Vigorous reflex movements could still be evoked, but these movements were unaccompanied by cerebellar tremor. On the basis of their results and of the observations of Munk,2of Dusser de Barenne3and of Walshe,4who showed in man that cerebellar tremor is present only in voluntary movements, it was concluded that the nervous mechanism involved in the phenomenon of cerebellar tremor includes some part of the cerebral hemispheres. The present paper will offer