The importance of those as yet little understood food factors popularly termed vitamins has become well established in the minds of persons who discuss dietetics from a scientific standpoint. Owing to the historical development, we presume, of our knowledge of the subject, milk and its products have heretofore furnished the chief topic of discussion in relation to vitamins. Thus it is now understood that the secretion of the mammary gland includes, in addition to such excellent nutrients as proteins, fats, sugar, salts of lime and other elements, constituents that promote nutrition and growth and, if properly conserved, suffice to avert scurvy in those individuals that depend on milk as the sole or preponderating source of their nourishment. Dietary analysis, as it is now practiced through actual feeding trials by investigators of nutrition, has assumed the existence of several types of vitamins in milk: the water-soluble, the fat-soluble, and the antiscorbutic