HEMOGLOBIN 



139 



Most noteworthy substances in this table are the nuclein and histon, 

 first isolated by Kossel and Lillienfeld as nucleohiston. Besides the 

 substances in the table, the white corpuscles contain salts of potassium, 

 sodium, calcium, and magnesium, with potassium phosphate present in 

 greatest amount. 



The Composition of the Red Corpuscles. Analysis of moist blood 

 corpuscles shows the following results: 



Water 68.8 per cent. 



Solids- 

 Organic 30-388 



Mineral.. 0.812 f 3I ' 2 



Of the solids the most important is the respiratory pigment, hemoglobin, 

 the substance to which the blood owes its color. It constitutes, as will be 

 seen from the appended table, more than 90 per cent, of the organic matter 

 of the corpuscles. Besides hemoglobin the corpuscles contain protein and 

 fatty matters, the former chiefly consisting of globulins, and the latter of 

 cholesterol and lecithin. 



In 100 parts of organic matter are found: 



Hemoglobin 90 . 54 per cent. 



Proteins 8.67 per cent. 



Fats o . 79 per cent. 



100.0 



The inorganic salts of the red corpuscles differ from the salts of serum 

 in that the ash of corpuscles contains a high content of those salts that 

 tend to form fixed organic compounds. For example, iron is present as a 

 part of the hemoglobin molecule. There is an excess of potassium in 

 corpuscles, present in fixed organic compounds. Only a small amount 

 of sodium is present, and of calcium only a trace. 



Hemoglobin. Of the substances in the erythrocytes, by far the most 

 important from every point of view is the pigment, hemoglobin. It composes 

 about 90 per cent, of the total solids of the corpuscles; therefore, between 

 14 and 15 per cent, of the blood itself. Hemoglobin is the most complex 

 compound in the body, having a molecule of the enormous molecular weight 

 of 16,669. Hemoglobin is intimately distributed throughout the stroma of 

 the corpuscle, and when dissolved out it can be crystallized. 



Its percentage composition is C, 53.85; H, 7.32; N, 16.17; O, 21.84; 8,0.63 

 Fe, 0.42. Jacquet gives the empirical formula for the hemoglobin of the dog, 

 C7S8H 12 o5N 195 S 3 FeO 218 . The most interesting of the properties of hemo- 

 globin are its powers of crystallizing and its attraction for oxygen and other 

 gases under certain pressure relations. 



Hemoglobin Crystals. The hemoglobin (oxy hemoglobin) of the blood of 

 various animals possesses the power of crystallizing to very different ex- 



