1. Šimek, J., and Sedláček, J., Physiol. Bohemoslov. (in the press).
2. Harkness, R. D., J. Physiol. (London), 117, 267 (1952).
3. Grisham, J. W., Fed. Proc., 18, 478 (1959).
4. Recondo, A. M., and Frayssinet, C. H., J. Physiol. (Paris), 55, 242 (1963).
5. Krebs, H. A., and Johnson, W. A., Tabulae Biologicae, 9, pars 3 100 (1948).