From the theoretical point of view, the author discussed the relations between A: G ratio and K or Q and deduced the equation (5), (7), (8) or (8') in original text for them, whose correctness was proved by the application of these equations to the experimental results of Matuoka or Mukai et al. (cf. Fig. 1)As an empirical relation between R and Q, the author found the equation (9) in the original text, i. e.;log10R/Rn=constant×Q1/2 (See Fig. 2 and 3)It was shown that this empirical relation could be explained by theoretical relation (8'), provided that Δa, the deviation of % value of A-fraction from its normal average, was always proportional to Q1/2. The latter fact was also found actually in above-mentioned experimental results and might be explained by the assumption that albumin fraction played main rôle in the regulation of total amount of plasma plotein and it was pointed out that practical significance of R widely employed was mainly due to this fact.It was also made clear that Q was considebraly correlative with with E. S. R. or the state of patient. (cf. Fig. 4, 5, 6.)