1. Keller, M., and Weiss, J., J. Chem. Soc., 2709 (1950); 25, 1247 (1951).
2. Coleby, B., Keller, M., and Weiss, J., J. Chem. Soc., 66 (1954).
3. Barron, E. S. G., Radiation Research, 1, 109 (1954).
4. For experimental arrangements cf. Farmer, F. T., Stein, G., and Weiss, J., J. Chem. Soc., 3241 (1949).
5. Bush, I. E., Biochem. J., 50, 370 (1952).