VARIATION OF HEMOCYANIN CONCENTRATION IN THE BLOOD OF FOUR SPECIES OF HALIOTIS

¹ Division of Marine Biology, Scripps Institution of Oceanography, La Jolla, California

1. The concentration of non-protein nitrogen in plasma from four species of Haliotis was fairly constant with average values estimated as follows: H. fulgens, 9.9; H. cracherodii, 9.6; H. corrugata, 4.9 and H. rufescens, 7.0 mg./l00 ml.

2. The concentration of non-hemocyanin protein in plasma was fairly constant. and quite low, in three of the species studied. Average values, expressed as gm./100 ml., were: H. fulgens, 0.20; H. cracherodii, 0.14; H. corrugata, 0.24. Plasma from H. rufescens contained low but variable quantities of non-hemocyanin protein.

3. Hemocyanin was present in abalone plasma in greatly varying concentrations. The median hemocyanin concentration in the plasma of 107 individuals of the species H. fulgens was 0.54 gm./100 ml., and the range was 0.03 to 1.89 gm./l00 ml. This is a 63-fold variation in concentration.

4. Plasma from H. corrugata, H. cracherodii and H. rufescens also had varying concentrations of hemocyanin. Plasma from 26 individuals of H. corrugata had a median concentration of 0.15 gm./l00 ml., and seven individuals of H. cracherodii had a median hemocyanin concentration of 0.38 gm./100 ml. The corresponding ranges were 0.0017 to 1.53, and 0.210 to 2.03 gm./l00 ml., respectively, giving a 900-fold and a 10-fold range between the highest and lowest samples. No similar information is available for other species of molluscs.

5. The concentration of hemocyanin was unrelated to the animal's weight, sex, reproductive activity, as judged by the gonad index, nutritional state, the depth in the water at which the animal had been collected, or the season of the year.

6. This enormous range in concentration of hemocyanin in the blood appears to be incompatible with any physiological function which has so far been suggested.