The output of vitamin A in eggs, calculated as the percentage of that consumed, varied from 11 to 32 per cent, and was determined by the number of units of the factor consumed, the number of eggs produced and the potency of the yolk. The highest percentages were obtained during high production. The liver vitamin A of the hens varied inversely with egg production. In the case of vitamin D the amount of the factor which appeared in the eggs was 10 per cent of that consumed. The data suggest that sunlight is more effective in increasing the antirachitic potency of egg yolk than the amount of cod liver oil ordinarily fed.