This investigator further pointed out that the nervous symptoms of polyneuritic birds may be rapidly ameliorated or recovered from and yet these birds may die as the result of the gastro-intestinal lesions. He emphasized that the rapid recovery from the nervous symptoms indicated that of all the tissues, the nerves are least affected as regards organic lesions by vitamin deficiency. Much more serious damage resulted to the intestine, and recovery from these lesions was correspondingly slow. The remarkably rapid disappearance of convulsive seizures, of astasia and of cerebellar symptoms, indicated clearly that specific fasting for the anti-neuritic substance was in some manner intimately concerned with the functioning of the nervous system. According to McCarrison, this may be an activation or energizing action on the nerve cells, or a necessary condition for the completion of the nervous current. Certain it is that in the absence of this substance, the nerve cells are incapable of normal activity, and when it is provided, normal functioning is reestablished with dramatic suddenness. McCarrison accepts the view, expressed by Bayliss, that the function of the anti-neuritic substance is that of a catalyst.