Further evidence for a third accessory “B” factor

IN a recent publication [Reader, 1929] evidence was presented for the division of the vitamin-B complex into three components all necessary for the nutrition of the rat. It was shown that two of these were destroyed by autoclaving yeast extract at PH 9 for one hour at 1200. Further evidence has now been obtained for the separate existence of these three factors, since it has been possible to concentrate two of them, and to find that the third must still be added to enable the animals to grow to maximum adult size.