In a previous study of the nitrogen metabolism of premature infants,1 attention was called to the defective ability of such infants to absorb fat. This defect had been noted earlier by Rubner and Langstein,2 by Muhl3 and by Holt and his co-workers 4 and was considered by Ylpp\l=o"\ 5 to be a factor contributing to the tendency for rickets to develop in premature infants. In a subsequent study of the energy exchange of premature infants,6 the loss of calories in the feces was found to be two to three times that reported for full term infants. It was suggested that the use for premature infants of a feeding mixture from which Assistance in this work was given by the Children's Bureau of the U. S.