In earlier work on the nitrogen metabolism of the young calf (Blaxter & Wood, 1951 a, c) the sole source of vitamin E in the diets was high-quality dried skim milk that had been packed in sealed tins. At the time it was thought that this source of vitamin E activity would be sufficient to protect the animal during the short-term experiments envisaged, especially in view of the very considerable difficulties that have been met in devising cattle diets containing little vitamin E (Gullickson, Palmer, Boyd, Nelson, Olson, Calverley & Boyer, 1949; Gullickson & Calverley, 1946). One of our early experiments, however, had to be abandoned owing to the onset of a syndrome in which vitamin E appeared to be involved.Six animals were affected 24-60 days after birth. The animals became very weak and unwilling to stand for more than a few minutes; the pastern joints became straightened ; the hind-legs crossed when attempts to walk were made ; there was a general ataxia, and the neck was outstretched in a very characteristic way. A tetany, not involving the extremities, was common during the latter stages and was seen only when the severely affected animal was placed on its feet. Relaxation of the musculature of the throat and inability to control movements of the tongue made drinking difficult and, in the terminal stages, the calves choked, owing to liquid food entering the trachea. Loss of hair at the bulbal base of the ear was always a common feature; the coat was staring and the skin thickened, the latter making superficial venesection difficult. I n two animals oedema of the brisket and ascites were present. This was of rapid onset as judged by gains in body-weight and seemed to be associated with a slight exophthalmos. In these oedematous calves the pulse was highly erratic and generally increased in frequency. Death occurred suddenly if such signs of cardiac abnormality were present; otherwise the animals died following a period of prostration. At post-mortem examination ascitic fluid was found in the abdominal cavity, the carcass was generally slightly oedematous, and one constant feature was the rapidity of putrefactive change. The liver and kidneys were normal; the lungs were pneumonic and contained milk and blood. The heart was dilated in some animals, and slight white lesions were found in the walls of the left ventricle in one of those animals affected by oedema. The bones were calcified quite normally but some erosion of the articular cartilages was present. This, however, was also found in normal calves. The skeletal muscle was very pale and flabby, and the fat was a light