1. BEECHER, H. K., FOLLANSBEE, R., MURPHY, A. J., and CRAIG, F. N. (1942). J. biol. Chem.
2. BERGGREN, S. M. (1942). Acta physiol. scand., 4, Suppl. 11.
3. CHRISTIANSEN, G. S., and LEINFELDER, P. J. (1952). Amer. J. Ophthal, 35, (pt 2) 21.
4. ELY, L. 0. (1949). Ibid., 32, June (pt 2) 220.
5. FIELD, J., TAINTER, E. G., MARTIN, A. W., and BELDING, H. S. (1937). Ibid., 20, 779.