XXV quality as used for medicinal purposes, was found to contain 10.2 mg a-tocopherol/ IOO g. With their diet containing 10% of this oil it may be calculated that our rats received at least 0.7 mg of a-tocopherol weekly from this source. This intake may be compared with a minimal requirement of about 0.3 mg necessary to prevent signs of deficiency when the diet contains lard instead of cod-liver oil, The effect of cod-liver oil in preventing or inducing the signs of avitaminosis E differed decidedly according to the particular sign which was under consideration. Thus cod-liver oil, presumably by virtue of its vitamin E content, gave complete protection, at least for several months, against brown discoloration of the uterus and degeneration of the testes. No protection was given, however, against brown discoloration of the body fat, haemolysis by dialuric acid, or post-mortem autolysis in the kidneys. I n females which had received diets containing either cod-liver oil or lard for about 5 months striking contrasts were seen between the uterus and the fat deposits attached to this organ. With lard in the diet the uterus was brown, while the adjoining fat deposits were white. With cod-liver oil in the diet the fat was a deep brown, but the colour of the uterus was normal. It appears, therefore, that the results of the antagonism between vitamin E and highly unsaturated fatty acids, when both are supplied in the form of cod-liver oil, are widely divergent in different parts of the body. co,.