“…In the outstanding experiments of Reyniers and his school (39,40) and of Gustafsson(4l) on germ-free rearing of animals, milk and its products and cream formed the basis of rearing mixtures for rats, whether germ-free or not, and were included in other diets.. Milk is strongly protective against caries in the ordinary rat (42) and in the cotton rat (43), much more markedly so in the liquid than in the dry form (44). However, paper (45) seemingly contradicts both findings for the cotton rat.…”