It is not advisable to enter into a discussion of these findings at the present time, owing to the lack of experimental evidence as to the exact nature of the vacuoles. Regardless of the nature of these bodies or of what factors produce them, they are structures abnormal to the connective tissue cells. The lack of dextrose in the medium of tissue cultures leads to some condition distinctly detrimental to the cells, resulting in their vacuolation and death, even when the medium contains abundant protein material. The addition of small amounts (0.5 to 1 per cent) of dextrose to the medium delays the formation of vacuoles and prolongs the life of the culture. The addition of large amounts (2 to 5 per cent) prevents vacuolation of the cells, but so much dextrose usually leads to a change in the hydrogen ion concentration of the culture resulting in an acid condition which arises coincidentally with the degeneration of the cells.