While engaged in studying experimentally the connections of the cells of Clarke’s column with the ascending tracts of the spinal cord in the Monkey, I was surprised to find that after hemisection in the lower dorsal region, the sensory disturbances produced in no way corresponded with those already obtained by an eminent observer. I was, therefore, led to continue my experiments, with the aid of a grant from the British Medical Association, and by the kind permission of Professor Schäfer I carried them out in the Physiological Laboratory of University College. My thanks are also due to him for much valuable advice and assistance.